Foods that Affect Testosterone Levels

Foods that Affect Testosterone Levels.jpeg

A number of studies suggest that exposure to industrial pollutants may affect sexual function, for example, loss of libido, sexual dysfunction, and impotence. This may be due to effects on testosterone levels. In a study of men who ate a lot of contaminated fish, an elevation in PCB levels in the blood was associated with a lower concentration of testosterone levels. These pollutants are found predominantly in fish, but also meat and dairy. The lowest levels are found in plants (see Dietary Pollutants May Affect Testosterone Levels).

Testosterone doesn't just play a role in the determination of secondary sex characteristics like facial hair at puberty. It also regulates normal sexual functioning and the overall physical and psychological well-being of adult men. Abnormally low levels of testosterone can lead to decreased physical endurance and memory capacity, loss of libido, drop in sperm count, loss of bone density, obesity, and depression.

Endocrine-disrupting compounds that build up in fish may be able to mimic or block hormone receptors, or alter rates of synthesis or breakdown of sex steroid hormones. In children, these pollutants may actually impair sexual development. Boys who are exposed may grow up with smaller penises (although only by about two-thirds of an inch shorter at most). Researchers have tried exposing cells from aborted fetal human penises to these kinds of dietary pollutants, and gene expression related to genital development is indeed affected at real-life exposure levels. We're not sure if the effects on penis length are due to the pro-estrogenic effects of the toxins, though, or the anti-testosterone effects.

You've heard of save the whales? Well, male reproductive organs may be at risk from environmental hazards as well.

I previously addressed how we discovered the endocrine disruptor phenomenon in Alkylphenol Endocrine Disruptors and Allergies, as well as where they're found (Dietary Sources of Alkylphenol Endocrine Disruptors).

For more on sustaining male virility, see Male Fertility and Diet, The Role of Diet in Declining Sperm Counts, and Dairy Estrogen and Male Fertility.

I've talked about the role a plastics chemical may play in male sexual functioning (BPA Plastic and Male Sexual Dysfunction). But it's not just toxins, it's the total diet (Survival of the Firmest: Erectile Dysfunction and Death), and not only in men (Cholesterol and Female Sexual Dysfunction). My latest on the topic is Best Foods to Improve Sexual Function.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. Image has been modified.

Original Link

Foods that Affect Testosterone Levels

Foods that Affect Testosterone Levels.jpeg

A number of studies suggest that exposure to industrial pollutants may affect sexual function, for example, loss of libido, sexual dysfunction, and impotence. This may be due to effects on testosterone levels. In a study of men who ate a lot of contaminated fish, an elevation in PCB levels in the blood was associated with a lower concentration of testosterone levels. These pollutants are found predominantly in fish, but also meat and dairy. The lowest levels are found in plants (see Dietary Pollutants May Affect Testosterone Levels).

Testosterone doesn't just play a role in the determination of secondary sex characteristics like facial hair at puberty. It also regulates normal sexual functioning and the overall physical and psychological well-being of adult men. Abnormally low levels of testosterone can lead to decreased physical endurance and memory capacity, loss of libido, drop in sperm count, loss of bone density, obesity, and depression.

Endocrine-disrupting compounds that build up in fish may be able to mimic or block hormone receptors, or alter rates of synthesis or breakdown of sex steroid hormones. In children, these pollutants may actually impair sexual development. Boys who are exposed may grow up with smaller penises (although only by about two-thirds of an inch shorter at most). Researchers have tried exposing cells from aborted fetal human penises to these kinds of dietary pollutants, and gene expression related to genital development is indeed affected at real-life exposure levels. We're not sure if the effects on penis length are due to the pro-estrogenic effects of the toxins, though, or the anti-testosterone effects.

You've heard of save the whales? Well, male reproductive organs may be at risk from environmental hazards as well.

I previously addressed how we discovered the endocrine disruptor phenomenon in Alkylphenol Endocrine Disruptors and Allergies, as well as where they're found (Dietary Sources of Alkylphenol Endocrine Disruptors).

For more on sustaining male virility, see Male Fertility and Diet, The Role of Diet in Declining Sperm Counts, and Dairy Estrogen and Male Fertility.

I've talked about the role a plastics chemical may play in male sexual functioning (BPA Plastic and Male Sexual Dysfunction). But it's not just toxins, it's the total diet (Survival of the Firmest: Erectile Dysfunction and Death), and not only in men (Cholesterol and Female Sexual Dysfunction). My latest on the topic is Best Foods to Improve Sexual Function.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. Image has been modified.

Original Link

Antioxidant- and Folate-Rich Foods for Depression

Antioxidant- and Folate-Rich Foods for Depression.jpeg

According to the Centers for Disease Control and Prevention, the rates of all of our top 10 killers have fallen or stabilized except for one, suicide. As shown in my video, Antioxidants & Depression, accumulating evidence indicates that free radicals may play important roles in the development of various neuropsychiatric disorders including major depression, a common cause of suicide.

In a study of nearly 300,000 Canadians, for example, greater fruit and vegetable consumption was associated with lower odds of depression, psychological distress, self-reported mood and anxiety disorders and poor perceived mental health. They conclude that since a healthy diet comprised of a high intake of fruits and vegetables is rich in anti-oxidants, it may consequently dampen the detrimental effects of oxidative stress on mental health.

But that study was based on asking how many fruits and veggies people ate. Maybe people were just telling the researchers what they thought they wanted to hear. What if you actually measure the levels of carotenoid phytonutrients in people's bloodstreams? The same relationship is found. Testing nearly 2000 people across the United States, researchers found that a higher total blood carotenoid level was indeed associated with a lower likelihood of elevated depressive symptoms, and there appeared to be a dose-response relationship, meaning the higher the levels, the better people felt.

Lycopene, the red pigment predominantly found in tomatoes (but also present in watermelon, pink grapefruit, guava and papaya) is the most powerful carotenoid antioxidant. In a test tube, it's about 100 times more effective at quenching free radicals than a more familiar antioxidant like vitamin E.

Do people who eat more tomatoes have less depression, then? Apparently so. A study of about a thousand older men and women found that those who ate the most tomato products had only about half the odds of depression. The researchers conclude that a tomato-rich diet may have a beneficial effect on the prevention of depressive symptoms.

Higher consumption of fruits and vegetables has been found to lead to a lower risk of developing depression, but if it's the antioxidants can't we just take an antioxidant pill? No.

Only food sources of antioxidants were protectively associated with depression. Not antioxidants from dietary supplements. Although plant foods and food-derived phytochemicals have been associated with health benefits, antioxidants from dietary supplements appear to be less beneficial and may, in fact, be detrimental to health. This may indicate that the form and delivery of the antioxidants are important. Alternatively, the observed associations may be due not to antioxidants but rather to other dietary factors, such as folate, that also occur in plant-rich diets.

In a study of thousands of middle-aged office workers, eating lots of processed food was found to be a risk factor for at least mild to moderate depression five years later, whereas a whole food pattern was found to be protective. Yes, it could be because of the high content of antioxidants in fruits and vegetables but could also be the folate in greens and beans, as some studies have suggested an increased risk of depression in folks who may not have been eating enough.

Low folate levels in the blood are associated with depression, but since most of the early studies were cross-sectional, meaning a snapshot in time, we didn't know if the low folate led to depression or the depression led to low folate. Maybe when you have the blues you don't want to eat the greens.

But since then a number of cohort studies were published, following people over time. They show that a low dietary intake of folate may indeed be a risk factor for severe depression, as much as a threefold higher risk. Note this is for dietary folate intake, not folic acid supplements; those with higher levels were actually eating healthy foods. If you give people folic acid pills they don't seem to work. This may be because folate is found in dark green leafy vegetables like spinach, whereas folic acid is the oxidized synthetic compound used in food fortification and dietary supplements because it's more shelf-stable. It may have different effects on the body as I previously explored in Can Folic Acid Be Harmful?

These kinds of findings point to the importance of antioxidant food sources rather than dietary supplements. But there was an interesting study giving people high dose vitamin C. In contrast to the placebo group, those given vitamin C experienced a decrease in depression scores and also greater FSI. What is FSI? Frequency of Sexual Intercourse.

Evidently, high dose vitamin C improves mood and intercourse frequency, but only in sexual partners that don't live with one another. In the placebo group, those not living together had sex about once a week, and those living together a little higher, once every five days, with no big change on vitamin C. But for those not living together, on vitamin C? Every other day! The differential effect for non-cohabitants suggests that the mechanism is not a peripheral one, meaning outside the brain, but a central one--some psychological change which motivates the person to venture forth to have intercourse. The mild antidepressant effect they found was unrelated to cohabitation or frequency, so it does not appear that the depression scores improved just because of the improved FSI.

For more mental health video, see:

Anything else we can do to enhance our sexual health and attractiveness? See:

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

Antioxidant- and Folate-Rich Foods for Depression

Antioxidant- and Folate-Rich Foods for Depression.jpeg

According to the Centers for Disease Control and Prevention, the rates of all of our top 10 killers have fallen or stabilized except for one, suicide. As shown in my video, Antioxidants & Depression, accumulating evidence indicates that free radicals may play important roles in the development of various neuropsychiatric disorders including major depression, a common cause of suicide.

In a study of nearly 300,000 Canadians, for example, greater fruit and vegetable consumption was associated with lower odds of depression, psychological distress, self-reported mood and anxiety disorders and poor perceived mental health. They conclude that since a healthy diet comprised of a high intake of fruits and vegetables is rich in anti-oxidants, it may consequently dampen the detrimental effects of oxidative stress on mental health.

But that study was based on asking how many fruits and veggies people ate. Maybe people were just telling the researchers what they thought they wanted to hear. What if you actually measure the levels of carotenoid phytonutrients in people's bloodstreams? The same relationship is found. Testing nearly 2000 people across the United States, researchers found that a higher total blood carotenoid level was indeed associated with a lower likelihood of elevated depressive symptoms, and there appeared to be a dose-response relationship, meaning the higher the levels, the better people felt.

Lycopene, the red pigment predominantly found in tomatoes (but also present in watermelon, pink grapefruit, guava and papaya) is the most powerful carotenoid antioxidant. In a test tube, it's about 100 times more effective at quenching free radicals than a more familiar antioxidant like vitamin E.

Do people who eat more tomatoes have less depression, then? Apparently so. A study of about a thousand older men and women found that those who ate the most tomato products had only about half the odds of depression. The researchers conclude that a tomato-rich diet may have a beneficial effect on the prevention of depressive symptoms.

Higher consumption of fruits and vegetables has been found to lead to a lower risk of developing depression, but if it's the antioxidants can't we just take an antioxidant pill? No.

Only food sources of antioxidants were protectively associated with depression. Not antioxidants from dietary supplements. Although plant foods and food-derived phytochemicals have been associated with health benefits, antioxidants from dietary supplements appear to be less beneficial and may, in fact, be detrimental to health. This may indicate that the form and delivery of the antioxidants are important. Alternatively, the observed associations may be due not to antioxidants but rather to other dietary factors, such as folate, that also occur in plant-rich diets.

In a study of thousands of middle-aged office workers, eating lots of processed food was found to be a risk factor for at least mild to moderate depression five years later, whereas a whole food pattern was found to be protective. Yes, it could be because of the high content of antioxidants in fruits and vegetables but could also be the folate in greens and beans, as some studies have suggested an increased risk of depression in folks who may not have been eating enough.

Low folate levels in the blood are associated with depression, but since most of the early studies were cross-sectional, meaning a snapshot in time, we didn't know if the low folate led to depression or the depression led to low folate. Maybe when you have the blues you don't want to eat the greens.

But since then a number of cohort studies were published, following people over time. They show that a low dietary intake of folate may indeed be a risk factor for severe depression, as much as a threefold higher risk. Note this is for dietary folate intake, not folic acid supplements; those with higher levels were actually eating healthy foods. If you give people folic acid pills they don't seem to work. This may be because folate is found in dark green leafy vegetables like spinach, whereas folic acid is the oxidized synthetic compound used in food fortification and dietary supplements because it's more shelf-stable. It may have different effects on the body as I previously explored in Can Folic Acid Be Harmful?

These kinds of findings point to the importance of antioxidant food sources rather than dietary supplements. But there was an interesting study giving people high dose vitamin C. In contrast to the placebo group, those given vitamin C experienced a decrease in depression scores and also greater FSI. What is FSI? Frequency of Sexual Intercourse.

Evidently, high dose vitamin C improves mood and intercourse frequency, but only in sexual partners that don't live with one another. In the placebo group, those not living together had sex about once a week, and those living together a little higher, once every five days, with no big change on vitamin C. But for those not living together, on vitamin C? Every other day! The differential effect for non-cohabitants suggests that the mechanism is not a peripheral one, meaning outside the brain, but a central one--some psychological change which motivates the person to venture forth to have intercourse. The mild antidepressant effect they found was unrelated to cohabitation or frequency, so it does not appear that the depression scores improved just because of the improved FSI.

For more mental health video, see:

Anything else we can do to enhance our sexual health and attractiveness? See:

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

Are Sugar Pills Better than Antidepressant Drugs?

Do Antidepressant Drugs Really Work.jpg

We've learned that exercise compares favorably to antidepressant medications as a first-line treatment for mild to moderate depression (in my video Exercise vs. Drugs for Depression). But how much is that really saying? How effective are antidepressant drugs in the first place?

A recent meta-analysis sparked huge scientific and public controversy by stating that the placebo effect can explain the apparent clinical benefits of antidepressants. But aren't there thousands of clinical trials providing compelling evidence for antidepressant effectiveness? If a meta-analysis compiles together all the best published research, how could it say they don't work much better than sugar pills?

The key word is "published."

What if a drug company decided only to publish studies that showed a positive effect, but quietly shelved and concealed any studies showing the drug didn't work? If you didn't know any better, you'd look at the published medical literature and think "Wow, this drug is great." And what if all the drug companies did that? To find out if this was the case, researchers applied to the FDA under the Freedom of Information Act to get access to the published and unpublished studies submitted by pharmaceutical companies, and what they found was shocking.

According to the published literature, the results of nearly all the trials of antidepressants were positive, meaning they worked. In contrast, FDA analysis of the trial data showed only roughly half of the trials had positive results. In other words, about half the studies showed the drugs didn't work. Thus, when published and unpublished data are combined, they fail to show a clinically significant advantage for antidepressant medication over a sugar pill. Not publishing negative results undermines evidence-based medicine and puts millions of patients at risk for using ineffective or unsafe drugs, and this was the case with these antidepressant drugs.

These revelations hit first in 2008. Prozac, Serzone, Paxil and Effexor worked, but so did sugar pills, and the difference between the drug and placebo was small. That was 2008. Where were we by 2014? Analyses of the published data and the unpublished data that were hidden by drug companies reveals that most (if not all) of the benefits of antidepressants are due to the placebo effect. And what's even worse, Freedom of Information Act documents show the FDA knew about it but made an explicit decision to keep this information from the public and from prescribing physicians.

How could drug companies get away with this?

The pharmaceutical industry is considered the most profitable and politically influential industry in the United States, and mental illness can be thought of as the drug industry's golden goose: incurable, common, long term and involving multiple medications. Antidepressant medications are prescribed to 8.7 percent of the U.S. population. It's a multi-billion dollar market.

To summarize, there is a strong therapeutic response to antidepressant medication; it's just that the response to placebo is almost as strong. Indeed, antidepressants offer substantial benefits to millions of people suffering from depression, and to cast them as ineffective is inaccurate. Just because they may not work better than fake pills doesn't mean they don't work. It's like homeopathy--just because it doesn't work better than the sugar pills, doesn't mean that homeopathy doesn't work. The placebo effect is real and powerful.

In one psychopharmacology journal, a psychiatrist funded by the Prozac company defends the drugs stating, "A key issue is disregarded by the naysaying critics. If the patient is benefiting from antidepressant treatment does it matter whether this is being achieved via drug or placebo effects?"

Of course it matters!

Among the side effects of antidepressants are: sexual dysfunction in up to three quarters of people, long-term weight gain, insomnia, nausea and diarrhea. About one in five show withdrawal symptoms when they try to quit. And perhaps more tragically, the drugs may make people more likely to become depressed in the future. Let me say that again: People are more likely to become depressed after treatment by antidepressants than after treatment by other means - including placebo.

So if doctors are willing to give patients placebo-equivalent treatments, maybe it'd be better for them to just lie to patients and give them actual sugar pills. Yes, that involves deception, but isn't that preferable than deception with a side of side effects? See more on this in my video Do Antidepressant Drugs Really Work?

If different treatments are equally effective, then choice should be based on risk and harm, and of all of the available treatments, antidepressant drugs may be among the riskiest and most harmful. If they are to be used at all, it should be as a last resort, when depression is extremely severe and all other treatment alternatives have been tried and failed.

Antidepressants may not work better than placebo for mild and moderate depression, but for very severe depression, the drugs do beat out sugar pills. But that's just a small fraction of the people taking these drugs. That means that the vast majority of depressed patients--as many as nine out of ten--are being prescribed medications that have negligible benefits to them.

Too many doctors quickly decide upon a depression diagnosis without necessarily listening to what the patient has to say and end up putting them on antidepressants without considering alternatives. And fortunately, there are effective alternatives. Physical exercise, for example can have lasting effects, and if that turns out to also be a placebo effect, it is at least a placebo with an enviable list of side effects. Whereas side effects of antidepressants include things like sexual dysfunction and insomnia, side effects of exercise include enhanced libido, better sleep, decreased body fat, improved muscle tone and a longer life.


There are other ways meta-analyses can be misleading. See The Saturated Fat Studies: Buttering Up the Public and The Saturated Fat Studies: Set Up to Fail.

More on the ethical challenges facing doctors and whether or not to prescribe sugar pills in The Lie That Heals: Should Doctors Give Placebos?

I've used the Freedom of Information Act myself to get access to behind the scenes industry shenanigans. See, for example, what I found out about the egg industry in Who Says Eggs Aren't Healthy or Safe? and Eggs and Cholesterol: Patently False and Misleading Claims.

This isn't the only case of the medical profession overselling the benefits of drugs. See How Smoking in 1956 is Like Eating in 2016, The Actual Benefit of Diet vs. Drugs and Why Prevention is Worth a Ton of Cure (though if you're worried about your mood they might make you even more depressed!)

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: GraphicStock. This image has been modified.

Original Link

Are Sugar Pills Better than Antidepressant Drugs?

Do Antidepressant Drugs Really Work.jpg

We've learned that exercise compares favorably to antidepressant medications as a first-line treatment for mild to moderate depression (in my video Exercise vs. Drugs for Depression). But how much is that really saying? How effective are antidepressant drugs in the first place?

A recent meta-analysis sparked huge scientific and public controversy by stating that the placebo effect can explain the apparent clinical benefits of antidepressants. But aren't there thousands of clinical trials providing compelling evidence for antidepressant effectiveness? If a meta-analysis compiles together all the best published research, how could it say they don't work much better than sugar pills?

The key word is "published."

What if a drug company decided only to publish studies that showed a positive effect, but quietly shelved and concealed any studies showing the drug didn't work? If you didn't know any better, you'd look at the published medical literature and think "Wow, this drug is great." And what if all the drug companies did that? To find out if this was the case, researchers applied to the FDA under the Freedom of Information Act to get access to the published and unpublished studies submitted by pharmaceutical companies, and what they found was shocking.

According to the published literature, the results of nearly all the trials of antidepressants were positive, meaning they worked. In contrast, FDA analysis of the trial data showed only roughly half of the trials had positive results. In other words, about half the studies showed the drugs didn't work. Thus, when published and unpublished data are combined, they fail to show a clinically significant advantage for antidepressant medication over a sugar pill. Not publishing negative results undermines evidence-based medicine and puts millions of patients at risk for using ineffective or unsafe drugs, and this was the case with these antidepressant drugs.

These revelations hit first in 2008. Prozac, Serzone, Paxil and Effexor worked, but so did sugar pills, and the difference between the drug and placebo was small. That was 2008. Where were we by 2014? Analyses of the published data and the unpublished data that were hidden by drug companies reveals that most (if not all) of the benefits of antidepressants are due to the placebo effect. And what's even worse, Freedom of Information Act documents show the FDA knew about it but made an explicit decision to keep this information from the public and from prescribing physicians.

How could drug companies get away with this?

The pharmaceutical industry is considered the most profitable and politically influential industry in the United States, and mental illness can be thought of as the drug industry's golden goose: incurable, common, long term and involving multiple medications. Antidepressant medications are prescribed to 8.7 percent of the U.S. population. It's a multi-billion dollar market.

To summarize, there is a strong therapeutic response to antidepressant medication; it's just that the response to placebo is almost as strong. Indeed, antidepressants offer substantial benefits to millions of people suffering from depression, and to cast them as ineffective is inaccurate. Just because they may not work better than fake pills doesn't mean they don't work. It's like homeopathy--just because it doesn't work better than the sugar pills, doesn't mean that homeopathy doesn't work. The placebo effect is real and powerful.

In one psychopharmacology journal, a psychiatrist funded by the Prozac company defends the drugs stating, "A key issue is disregarded by the naysaying critics. If the patient is benefiting from antidepressant treatment does it matter whether this is being achieved via drug or placebo effects?"

Of course it matters!

Among the side effects of antidepressants are: sexual dysfunction in up to three quarters of people, long-term weight gain, insomnia, nausea and diarrhea. About one in five show withdrawal symptoms when they try to quit. And perhaps more tragically, the drugs may make people more likely to become depressed in the future. Let me say that again: People are more likely to become depressed after treatment by antidepressants than after treatment by other means - including placebo.

So if doctors are willing to give patients placebo-equivalent treatments, maybe it'd be better for them to just lie to patients and give them actual sugar pills. Yes, that involves deception, but isn't that preferable than deception with a side of side effects? See more on this in my video Do Antidepressant Drugs Really Work?

If different treatments are equally effective, then choice should be based on risk and harm, and of all of the available treatments, antidepressant drugs may be among the riskiest and most harmful. If they are to be used at all, it should be as a last resort, when depression is extremely severe and all other treatment alternatives have been tried and failed.

Antidepressants may not work better than placebo for mild and moderate depression, but for very severe depression, the drugs do beat out sugar pills. But that's just a small fraction of the people taking these drugs. That means that the vast majority of depressed patients--as many as nine out of ten--are being prescribed medications that have negligible benefits to them.

Too many doctors quickly decide upon a depression diagnosis without necessarily listening to what the patient has to say and end up putting them on antidepressants without considering alternatives. And fortunately, there are effective alternatives. Physical exercise, for example can have lasting effects, and if that turns out to also be a placebo effect, it is at least a placebo with an enviable list of side effects. Whereas side effects of antidepressants include things like sexual dysfunction and insomnia, side effects of exercise include enhanced libido, better sleep, decreased body fat, improved muscle tone and a longer life.


There are other ways meta-analyses can be misleading. See The Saturated Fat Studies: Buttering Up the Public and The Saturated Fat Studies: Set Up to Fail.

More on the ethical challenges facing doctors and whether or not to prescribe sugar pills in The Lie That Heals: Should Doctors Give Placebos?

I've used the Freedom of Information Act myself to get access to behind the scenes industry shenanigans. See, for example, what I found out about the egg industry in Who Says Eggs Aren't Healthy or Safe? and Eggs and Cholesterol: Patently False and Misleading Claims.

This isn't the only case of the medical profession overselling the benefits of drugs. See How Smoking in 1956 is Like Eating in 2016, The Actual Benefit of Diet vs. Drugs and Why Prevention is Worth a Ton of Cure (though if you're worried about your mood they might make you even more depressed!)

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: GraphicStock. This image has been modified.

Original Link

Exercise as a Treatment for Depression

 Exercise vs. Drugs for Depression.jpg

We've known for decades that even a single bout of exercise can elevate our mood, but could it be enough to be used as a treatment for major depression?

We've known that physical activity has been associated with decreased symptoms of depression. For example, if you look at a cross-section of 8,000 people across the country, those that exercised regularly were less likely to have a major depression diagnosis. That's just a snapshot in time, though. In that study, the researcher openly acknowledges this may be a case of reverse causation. Maybe exercise didn't cut down on depression, maybe depression cut down on exercise. The reason depression may be associated with low physical activity is that people may feel too lousy to get out of bed. What we've needed was an interventional study where you take people who are already depressed and randomize them into an exercise intervention.

That is what researchers from Duke University Medical Center did. They randomized men and women over age 50 with major depression to two groups: one who did an aerobic exercise program for four months and another that took an antidepressant drug called Zoloft. In my video Exercise vs. Drugs for Depression you can see a graph of their changes. Before exercise, their Hamilton Depression scores were up around 18 (anything over seven is considered depressed). Within four months, the drug group came down to normal, which are exactly what the drugs are supposed to do. What about the exercise-only group, though? Exercise had the same powerful effect.

The researchers concluded that an exercise training program may be considered an alternative to antidepressants for treatment of depression in older persons, given that they've shown that a group program of aerobic exercise is a feasible and effective treatment for depression, at least for older people.

Not so fast, though.

A "group program?" They had the exercise group folks come in three times a week for a group class. Maybe the only reason the exercise group got better is because they were forced to get out of bed and interact with people--maybe it was the social stimulation and had nothing to do with the actual exercise? Before you could definitively say that exercise can work as well as drugs, what we would need to see is the same study, but with an additional group who exercised alone with no extra social interaction. And those same Duke researchers did just that,

They created the largest exercise trial of patients with major depression conducted to date, and not just including older folks, but other adults as well with three different treatment groups this time: a home exercise group in addition to the supervised group exercise and the drug group as before.

And they all worked about just as well in terms of forcing the depression into remission. So we can say with confidence that exercise is comparable to antidepressant medication in the treatment of patients with major depressive disorder.

Putting all the best studies together, researchers indicate that exercise at least has a moderate antidepressant effect, and at best, exercise has a large effect on reductions in depression symptoms and could be categorized as a very useful and powerful intervention. Unfortunately, while studies support the use of exercise as a treatment for depression, exercise is rarely prescribed as a treatment for this common and debilitating problem.

Exercise may compare favorably to antidepressant medications as a first-line treatment for mild to moderate depression, but how much is that really saying? How effective are antidepressant drugs in the first place? Check out my video Do Antidepressant Drugs Really Work?

For dietary interventions that may improve mood, see:

Exercise can also help with ADHD (Treating ADHD Without Stimulants) and improve immunity (Preserving Immune Function in Athletes With Nutritional Yeast), not to mention extend our lives (Longer Life Within Walking Distance). But what we eat matters: Paleo Diets May Negate Benefits of Exercise.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

Exercise as a Treatment for Depression

 Exercise vs. Drugs for Depression.jpg

We've known for decades that even a single bout of exercise can elevate our mood, but could it be enough to be used as a treatment for major depression?

We've known that physical activity has been associated with decreased symptoms of depression. For example, if you look at a cross-section of 8,000 people across the country, those that exercised regularly were less likely to have a major depression diagnosis. That's just a snapshot in time, though. In that study, the researcher openly acknowledges this may be a case of reverse causation. Maybe exercise didn't cut down on depression, maybe depression cut down on exercise. The reason depression may be associated with low physical activity is that people may feel too lousy to get out of bed. What we've needed was an interventional study where you take people who are already depressed and randomize them into an exercise intervention.

That is what researchers from Duke University Medical Center did. They randomized men and women over age 50 with major depression to two groups: one who did an aerobic exercise program for four months and another that took an antidepressant drug called Zoloft. In my video Exercise vs. Drugs for Depression you can see a graph of their changes. Before exercise, their Hamilton Depression scores were up around 18 (anything over seven is considered depressed). Within four months, the drug group came down to normal, which are exactly what the drugs are supposed to do. What about the exercise-only group, though? Exercise had the same powerful effect.

The researchers concluded that an exercise training program may be considered an alternative to antidepressants for treatment of depression in older persons, given that they've shown that a group program of aerobic exercise is a feasible and effective treatment for depression, at least for older people.

Not so fast, though.

A "group program?" They had the exercise group folks come in three times a week for a group class. Maybe the only reason the exercise group got better is because they were forced to get out of bed and interact with people--maybe it was the social stimulation and had nothing to do with the actual exercise? Before you could definitively say that exercise can work as well as drugs, what we would need to see is the same study, but with an additional group who exercised alone with no extra social interaction. And those same Duke researchers did just that,

They created the largest exercise trial of patients with major depression conducted to date, and not just including older folks, but other adults as well with three different treatment groups this time: a home exercise group in addition to the supervised group exercise and the drug group as before.

And they all worked about just as well in terms of forcing the depression into remission. So we can say with confidence that exercise is comparable to antidepressant medication in the treatment of patients with major depressive disorder.

Putting all the best studies together, researchers indicate that exercise at least has a moderate antidepressant effect, and at best, exercise has a large effect on reductions in depression symptoms and could be categorized as a very useful and powerful intervention. Unfortunately, while studies support the use of exercise as a treatment for depression, exercise is rarely prescribed as a treatment for this common and debilitating problem.

Exercise may compare favorably to antidepressant medications as a first-line treatment for mild to moderate depression, but how much is that really saying? How effective are antidepressant drugs in the first place? Check out my video Do Antidepressant Drugs Really Work?

For dietary interventions that may improve mood, see:

Exercise can also help with ADHD (Treating ADHD Without Stimulants) and improve immunity (Preserving Immune Function in Athletes With Nutritional Yeast), not to mention extend our lives (Longer Life Within Walking Distance). But what we eat matters: Paleo Diets May Negate Benefits of Exercise.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

What’s the Mediterranean Diet’s Secret?

Why Was Heart Disease Rare in the Mediterranean?.jpg

The Mediterranean Diet is an "in" topic nowadays in both the medical literature and the lay media. As one researcher put it, "Uncritical laudatory coverage is common, but specifics are hard to come by: What is it? Where did it come from? Why is it good? Merits are rarely detailed; possible downsides are never mentioned." So, let's dig in....

After World War II, the government of Greece asked the Rockefeller foundation to come in and assess the situation. Impressed by the low rates of heart disease in the region, nutrition scientist Ancel Keys--after which "K" rations were named--initiated his famous seven countries study. In this study, he found the rate of fatal heart disease on the Greek isle of Crete was 20 times lower than in the United States. They also had the lowest cancer rates and fewest deaths overall. What were they eating? Their diets were more than 90% plant-based, which may explain why coronary heart disease was such a rarity. A rarity, that is, except for a small class of rich people whose diet differed from that of the general population--they ate meat every day instead of every week or two.

So, the heart of the Mediterranean diet is mainly plant-based, and low in meat and dairy, which Keys considered the "major villains in the diet" because of their saturated fat content. Unfortunately, no one is really eating the traditional Mediterranean diet anymore, even in the Mediterranean. The prevalence of coronary heart disease skyrocketed by an order of magnitude within a few decades in Crete, blamed on the increased consumption of meat and cheese at the expense of plant foods.

Everyone is talking about the Mediterranean diet, but few do it properly. People think of pizza or spaghetti with meat sauce, but while "Italian restaurants brag about the healthy measuring in diet, they serve a travesty of it." If no one's really eating this way anymore, how do you study it?

Researchers came up with a variety of Mediterranean diet adherence scoring systems to see if people who are eating more Mediterranean-ish do better. You get maximum points the more plant foods you eat, and effectively you get points deducted by eating just a single serving of meat or dairy a day. So it's no surprise those that eat relatively higher on the scale have a lower risk of heart disease, cancer, and death overall. After all, the Mediterranean diet can be considered to be a "near vegetarian" diet. "As such, it should be expected to produce the well-established health benefits of vegetarian diets." That is, less heart disease, cancer, death, and inflammation; improved arterial function; a lower risk of developing type 2 diabetes; a reduced risk for stroke, depression, and cognitive impairment.

How might it work? I've talked about the elegant studies showing that those who eat plant-based diets have more plant-based compounds, like aspirin, circulating within their systems. Polyphenol phytonutrients in plant foods are associated with a significantly lower risk of dying. Magnesium consumption is also associated with a significantly lower risk of dying, and is found in dark green leafy vegetables, as well as fruits, beans, nuts, soy, and whole grains.

Heme iron, on the other hand--the iron found in blood and muscle--acts as a pro-oxidant and appears to increase the risk of diabetes, whereas plant-based, non-heme iron appears safe. Similarly, with heart disease, animal-based iron was found to significantly increase the risk of coronary heart disease, our number one killer, but not plant-based iron. The Mediterranean diet is protective compared to the Standard American Diet--no question--but any diet rich in whole plant foods and low in animal-fat consumption could be expected to confer protection against many of our leading killers.

Here are some more videos on the Mediterranean Diet:

For more information on heme iron, see Risk Associated With Iron Supplements.

More on magnesium is found in How Do Nuts Prevent Sudden Cardiac Death? and Mineral of the Year--Magnesium.

And more on polyphenols can be seen in videos like How to Slow Brain Aging by Two Years and Juicing Removes More Than Just Fiber.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Couleur / Pixabay. This image has been modified.

Original Link

What’s the Mediterranean Diet’s Secret?

Why Was Heart Disease Rare in the Mediterranean?.jpg

The Mediterranean Diet is an "in" topic nowadays in both the medical literature and the lay media. As one researcher put it, "Uncritical laudatory coverage is common, but specifics are hard to come by: What is it? Where did it come from? Why is it good? Merits are rarely detailed; possible downsides are never mentioned." So, let's dig in....

After World War II, the government of Greece asked the Rockefeller foundation to come in and assess the situation. Impressed by the low rates of heart disease in the region, nutrition scientist Ancel Keys--after which "K" rations were named--initiated his famous seven countries study. In this study, he found the rate of fatal heart disease on the Greek isle of Crete was 20 times lower than in the United States. They also had the lowest cancer rates and fewest deaths overall. What were they eating? Their diets were more than 90% plant-based, which may explain why coronary heart disease was such a rarity. A rarity, that is, except for a small class of rich people whose diet differed from that of the general population--they ate meat every day instead of every week or two.

So, the heart of the Mediterranean diet is mainly plant-based, and low in meat and dairy, which Keys considered the "major villains in the diet" because of their saturated fat content. Unfortunately, no one is really eating the traditional Mediterranean diet anymore, even in the Mediterranean. The prevalence of coronary heart disease skyrocketed by an order of magnitude within a few decades in Crete, blamed on the increased consumption of meat and cheese at the expense of plant foods.

Everyone is talking about the Mediterranean diet, but few do it properly. People think of pizza or spaghetti with meat sauce, but while "Italian restaurants brag about the healthy measuring in diet, they serve a travesty of it." If no one's really eating this way anymore, how do you study it?

Researchers came up with a variety of Mediterranean diet adherence scoring systems to see if people who are eating more Mediterranean-ish do better. You get maximum points the more plant foods you eat, and effectively you get points deducted by eating just a single serving of meat or dairy a day. So it's no surprise those that eat relatively higher on the scale have a lower risk of heart disease, cancer, and death overall. After all, the Mediterranean diet can be considered to be a "near vegetarian" diet. "As such, it should be expected to produce the well-established health benefits of vegetarian diets." That is, less heart disease, cancer, death, and inflammation; improved arterial function; a lower risk of developing type 2 diabetes; a reduced risk for stroke, depression, and cognitive impairment.

How might it work? I've talked about the elegant studies showing that those who eat plant-based diets have more plant-based compounds, like aspirin, circulating within their systems. Polyphenol phytonutrients in plant foods are associated with a significantly lower risk of dying. Magnesium consumption is also associated with a significantly lower risk of dying, and is found in dark green leafy vegetables, as well as fruits, beans, nuts, soy, and whole grains.

Heme iron, on the other hand--the iron found in blood and muscle--acts as a pro-oxidant and appears to increase the risk of diabetes, whereas plant-based, non-heme iron appears safe. Similarly, with heart disease, animal-based iron was found to significantly increase the risk of coronary heart disease, our number one killer, but not plant-based iron. The Mediterranean diet is protective compared to the Standard American Diet--no question--but any diet rich in whole plant foods and low in animal-fat consumption could be expected to confer protection against many of our leading killers.

Here are some more videos on the Mediterranean Diet:

For more information on heme iron, see Risk Associated With Iron Supplements.

More on magnesium is found in How Do Nuts Prevent Sudden Cardiac Death? and Mineral of the Year--Magnesium.

And more on polyphenols can be seen in videos like How to Slow Brain Aging by Two Years and Juicing Removes More Than Just Fiber.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Couleur / Pixabay. This image has been modified.

Original Link