Organic versus Conventional: Which has More Nutrients?

Organic versus Conventional - Which has More Nutrients?.jpeg

Are organic foods safer and healthier than conventional alternatives? Those are two separate questions. Some consumers are interested in getting more nutrients; others are more concerned about getting fewer pesticides. Let's do nutrition first.

As seen in my video, Are Organic Foods More Nutritious?, hundreds of studies have been reviewed and researchers didn't find significant differences for most of the traditional nutrients like vitamins and minerals. They concluded that despite the widespread perception that organically produced foods are more nutritious, they didn't find robust evidence to support that perception. They did, however, find higher levels of phenolic phytonutrients in organic.

These so-called "secondary metabolites" of plants are thought to be behind many of the benefits ascribed to eating fruits and vegetables. Organic fruits and vegetables had between 19 and 69% more of a variety of these antioxidant compounds. The theory was that these phytonutrients are created by the plant for its own protection. For example, broccoli releases the bitter compounds like sulforaphane when the plant is chewed to ward off those who might eat it. Bugs take one bite and say, "Ew, this tastes like broccoli!" But pesticide-laden plants are bitten less by bugs and so may be churning out fewer of these compounds. Plants raised organically, on the other hand, are in a fight for their lives and may necessarily have to produce more protection. That was the theory anyway, but we don't have good evidence to back it up. The more likely reason has to do with the fertilizer; plants given high dose synthetic nitrogen fertilizers may divert more resources to growth rather than defense.

These antioxidants may protect the plant, but what about us? More antioxidant phytonutrients are found in organic vegetables and so yes, they displayed more antioxidant activity, but also more antimutagenic activity. Researchers exposed bacteria to a variety of mutagenic chemicals like benzopyrene, the polycyclic aromatic hydrocarbon found in barbecued meat, or IQ, the heterocyclic amine found in grilled/broiled/fried meats (as well as cigarette smoke), and there were fewer DNA mutations in the petri dishes where they added organic vegetables compared to the petri dishes where they added conventional vegetables.

Preventing DNA damage in bacteria is one thing, but what about effects on actual human cells? Organic strawberries may taste better, and have higher antioxidant activity and more phenolic phytonutrients, but what happens when you stack them up head-to-head against human cancer cells? Extracts from organically grown strawberries suppressed the growth of colon cancer cells and breast cancer cells significantly better than extracts from conventional strawberries. Now this was dripping strawberries onto cancer cells growing in a petri dish, but as I showed in Strawberries versus Esophageal Cancer, there are real life circumstances in which strawberries come into direct contact with cancerous and precancerous lesions, and so presumably organic strawberries would work even better, but they haven't yet been tested in clinical trials.

Although in vitro studies show higher antioxidant and antimutagenic activity as well as better inhibition of cancer cell proliferation, clinical studies on the impact of eating organic on human disease simply haven't been done. Based on antioxidant phytonutrient levels, organic produce may be considered 20 to 40% healthier, the equivalent of adding one or two serving's worth to a five-a-day regimen. But organic produce may be 40% more expensive, so for the same money you could just buy the extra servings worth of conventional produce. From a purely nutrients-per-dollar standpoint, it's not clear that organic foods are any better. But people often buy organic foods to avoid chemicals, not because they are more nutritious. For more on the best available science comparing the nutritional content, pesticide risk, heavy metal toxicity, and food poisoning risk of organic versus conventionally raised foods )including practical tips for making your own DIY fruit and veggie wash), see:

I imagine that the reaction to this series will be similar to that for the one I did on GMO foods, riling up critics on both sides of the debate:

More on the nutritional implications of stressed-out plants here:

Production method aside, in vitro, Which Fruit Fights Cancer Better?

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

Organic versus Conventional: Which has More Nutrients?

Organic versus Conventional - Which has More Nutrients?.jpeg

Are organic foods safer and healthier than conventional alternatives? Those are two separate questions. Some consumers are interested in getting more nutrients; others are more concerned about getting fewer pesticides. Let's do nutrition first.

As seen in my video, Are Organic Foods More Nutritious?, hundreds of studies have been reviewed and researchers didn't find significant differences for most of the traditional nutrients like vitamins and minerals. They concluded that despite the widespread perception that organically produced foods are more nutritious, they didn't find robust evidence to support that perception. They did, however, find higher levels of phenolic phytonutrients in organic.

These so-called "secondary metabolites" of plants are thought to be behind many of the benefits ascribed to eating fruits and vegetables. Organic fruits and vegetables had between 19 and 69% more of a variety of these antioxidant compounds. The theory was that these phytonutrients are created by the plant for its own protection. For example, broccoli releases the bitter compounds like sulforaphane when the plant is chewed to ward off those who might eat it. Bugs take one bite and say, "Ew, this tastes like broccoli!" But pesticide-laden plants are bitten less by bugs and so may be churning out fewer of these compounds. Plants raised organically, on the other hand, are in a fight for their lives and may necessarily have to produce more protection. That was the theory anyway, but we don't have good evidence to back it up. The more likely reason has to do with the fertilizer; plants given high dose synthetic nitrogen fertilizers may divert more resources to growth rather than defense.

These antioxidants may protect the plant, but what about us? More antioxidant phytonutrients are found in organic vegetables and so yes, they displayed more antioxidant activity, but also more antimutagenic activity. Researchers exposed bacteria to a variety of mutagenic chemicals like benzopyrene, the polycyclic aromatic hydrocarbon found in barbecued meat, or IQ, the heterocyclic amine found in grilled/broiled/fried meats (as well as cigarette smoke), and there were fewer DNA mutations in the petri dishes where they added organic vegetables compared to the petri dishes where they added conventional vegetables.

Preventing DNA damage in bacteria is one thing, but what about effects on actual human cells? Organic strawberries may taste better, and have higher antioxidant activity and more phenolic phytonutrients, but what happens when you stack them up head-to-head against human cancer cells? Extracts from organically grown strawberries suppressed the growth of colon cancer cells and breast cancer cells significantly better than extracts from conventional strawberries. Now this was dripping strawberries onto cancer cells growing in a petri dish, but as I showed in Strawberries versus Esophageal Cancer, there are real life circumstances in which strawberries come into direct contact with cancerous and precancerous lesions, and so presumably organic strawberries would work even better, but they haven't yet been tested in clinical trials.

Although in vitro studies show higher antioxidant and antimutagenic activity as well as better inhibition of cancer cell proliferation, clinical studies on the impact of eating organic on human disease simply haven't been done. Based on antioxidant phytonutrient levels, organic produce may be considered 20 to 40% healthier, the equivalent of adding one or two serving's worth to a five-a-day regimen. But organic produce may be 40% more expensive, so for the same money you could just buy the extra servings worth of conventional produce. From a purely nutrients-per-dollar standpoint, it's not clear that organic foods are any better. But people often buy organic foods to avoid chemicals, not because they are more nutritious. For more on the best available science comparing the nutritional content, pesticide risk, heavy metal toxicity, and food poisoning risk of organic versus conventionally raised foods )including practical tips for making your own DIY fruit and veggie wash), see:

I imagine that the reaction to this series will be similar to that for the one I did on GMO foods, riling up critics on both sides of the debate:

More on the nutritional implications of stressed-out plants here:

Production method aside, in vitro, Which Fruit Fights Cancer Better?

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 Sprouted Lentils Healthier Than Canned Lentils?

NF-Apr28 Cooked Beans or Sprouted Beans.jpeg

Beans, chickpeas, split peas and lentils are packed with nutrients and play a role in the prevention of chronic disease, but most can't be eaten raw. Some can be sprouted, though. Boiling is the most common cooking method, which is used for canned beans. Which is healthier, though, cooked or sprouted?

The easiest way to compare healthfulness is to measure nutrient levels--such as the anthocyanin pigments that make kidney beans so pretty--thought to account for some of beans' protective benefits against chronic disease. Sprouted beans have more of some anthocyanins, but less than others. We find this same pattern across the board with the other phenolic phytonutrients: sprouted beans have more of some, less of others. Because the positive effects of these compounds may be related to their antioxidant capacity, we can compare the overall antioxidant power of boiled versus sprouted beans. In that case, boiled appears to have a marginal edge.

Ideally, though, rather than merely comparing concentrations of phytochemicals, we'd measure physiological effects. For example, we might look at the effect of boiled versus sprouted beans against cancer cell growth. That's exactly what researchers did. In my video Cooked Beans or Sprouted Beans?, you can see the concentrations of bean extract needed to cut the breast cancer growth rate in half in a petri dish. Boiled beans do about 40 times better than raw beans--the same cancer growth inhibition at just a fraction of the concentration. Sprouted beans do about the same.

We can't eat most beans raw, but I wanted to include them to show you a fascinating phenomenon. No amount of raw bean extract appears to totally stop the growth of breast cancer cells, but just small amounts of cooked or sprouted beans can. We find the same thing with killing off cancer. No amount of raw bean extract can fully kill off breast cancer cells, but both boiled and sprouted beans can.

Similar results were found for melanoma cells, a type of malignant skin cancer. Processing the beans--either cooking or sprouting--boosted anticancer activity in vitro. However, against kidney cancer, raw and boiled worked, but sprouted didn't at all.

There has also been interest in brain protection. Given that elderly persons who report always eating legumes may be significantly less likely to experience cognitive decline, a group of Chinese researchers decided to compare the protective effects of boiled versus sprouted beans on astrocytes.

Astrocytes are the most abundant type of cell in our brain. They are star-shaped cells that keep our brain running smoothly. Should they become damaged, though, they may play an important role in the development of neurodegenerative disorders such as Lou Gehrig's disease, Alzheimer's, or Parkinson's. So if we're thinking clearly, we should thank our lucky stars.

To see if beans help protect astrocytes from damage, we'd have to first make sure bean extracts wouldn't cause any damage. Cooked beans don't seem to hurt cells at all, and sprouted beans seem to even help them grow a little. If we add an oxidative chemical to the cells, we can kill off about a quarter of them. However, if we add that chemical along with some boiled bean extract, the astrocytes were partially protected at higher doses. Sprouted bean extract didn't appear to offer significant benefit.

What's the takeaway? As far as I'm concerned, we should eat beans in whichever way will get us to eat the most of them.

I do love my lentil sprouts, one of the healthiest snacks on the planet (along with kale chips). I can grow my own in just 2 to 3 days. But using canned beans I can get similar nutrition in about 2 to 3 seconds.

Sprouting is so much fun, though! I've got a bunch of videos on broccoli sprouts, for example: Biggest Nutrition Bang for Your Buck.

But again, whichever way we like them we should eat them. Why? See:

Mostly I just used canned. See Canned Beans or Cooked Beans?

Other videos on practical prep tips include:

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 Uprooting the Leading Causes of Death, More Than an Apple a Day, From Table to Able, and Food as Medicine.

Image Credit: Veganbaking.net / Flickr

Original Link