Nutritionally-oriented physician and best-selling author Joel Fuhrman, M.D., answers our questions about food quality in general, and a raw vegan diet.
Joel Fuhrman, M.D.
RawFoodsNewsMagazine: What are your thoughts on alkaline vs. acid foods?
Joel Fuhrman, M.D.: A food will either promote production of acids or bases in the body, based on its amino acid profile and protein and mineral content. Alkaline-forming foods are generally those that promote overall health: vegetables, fruits, and most other whole plant foods. For example, fruits and vegetables are generally alkaline-forming, while meat and cheese are acid-forming.It is not merely the acid in the food itself, but when you eat lots of animal products more acids are generated by the body to digest them.A plant-centered, healthy nutritarian diet is already alkaline forming and no special attention or consumption of alkaline waters or special alkaline foods are necessary to make it more so.Acid residue plant foods need not be avoided, since the diet is overall alkaline. The alkalinity of your diet is only one of many features of a healthy diet and not the defining feature of a longevity-promoting diet.
What percentage of a nutritarian diet/lifestyle are fresh raw (uncooked) vegetables and fruits?
Raw vegetables are the most powerful anti-cancer and lifespan promoting foods. What I advocate is a vegetable-based diet, and I encourage people to start both lunch and dinner with a large raw salad or some raw vegetables. I also encourage eating at least three fresh fruits each day, especially berries and pomegranate and raw seeds and nuts. Some beneficial nutrients, phytochemicals and enzymes in vegetables are lost or destroyed in high heat cooking, whereas others are made more bioavailable by cooking. For example, vitamin C is reduced when vegetables are cooked, but lycopene is dramatically more bioavailable in cooked tomatoes compared to raw. I recommend a combination of raw and cooked foods, though raw foods predominate by volume. I also recommend using water-based cooking, especially soups and stews and wokking rather than steaming, to retain nutrients in the cooking water. Beans and mushrooms are also better eaten cooked and add tremendous anti-cancer and lifespan-enhancing benefits. By eating only raw foods, you reduce the nutritional quality and variety of the diet. So a nutritarian diet can be mostly raw, but I see no health benefit, and it is more likely a disadvantage striving to make it 100 percent raw.
What are the health benefits of beans (specifically, what is a raw vegan diet missing because it does not include cooked beans)? And would sprouted legumes supply the same nutrients as cooked beans?
Beans and other legumes are a nutrient-dense, high fiber, carbohydrate source. Beans contain much more fiber and resistant starch than whole grains, and since they are digested slowly, they help to stabilize blood sugar, promote meal satisfaction and prevent food cravings. This also makes them tremendous anti-diabetes and weight-loss foods. On top of this, due to their soluble fiber content they help lower cholesterol levels. Beans and other legumes are especially rich in resistant starch , which is not broken down by digestive enzymes. This means that the total number of calories in beans and legumes are not absorbed, which is helpful for maintaining a healthy weight. Even more important, fiber and resistant starch are fermented by intestinal bacteria into short chain fatty acids, which protect against colon cancer. Eating beans and other legumes has also shown to be protective against several other cancers. Besides their direct health benefits, the indirect benefits mean that you eat less glycemic carbohydrates, particularly less fruit when your diet contains more calories from beans. In other words, a main disadvantage of a raw food diet is too high a percent of simple sugar calories from fruit. Beans enable us to get more calories, without exposure to more simple sugars.
Sprouting legumes changes the nutritional content, increasing vitamins and protein, and reducing carbohydrate, and calories, which makes sprouts more like a raw vegetable. Certainly bean sprouts are healthy, but that still doesn’t mean one shouldn’t eat cooked, non-sprouted beans. In other words, the main issue here is that there is no justification to make a diet so restrictive that a person should be afraid of eating a cooked bean.
What can all of us do to avoid cadmium and arsenic in our foods? Studies have found high levels of cadmium in sunflower seeds and raw cacao powders, for example. And studies have shown that rice contains high levels of arsenic. (I mention the rice even though raw vegans do not eat rice, because nutritarians eat rice.) And how do we even know what heavy metals might be in other foods that we're eating?
Cadmium levels in foods depend on soil levels and other growing conditions; phosphate fertilizers are a major contributor. Agricultural efforts to limit cadmium in soil are being undertaken. One thing we can do to limit our absorption of cadmium from foods is to eat a varied diet that includes adequate minerals. Iron, calcium and zinc can help to reduce absorption of cadmium; Plant foods contain sufficient of iron and calcium, however vegetarians and vegans should consider supplementing with zinc. Beans also contain phytic acid which helps binds and remove lead and cadmium.
Inorganic arsenic is a carcinogen, and this has become a concern because the FDA has found high levels of arsenic in rice, especially commercially grown brown rice. Since this is specific to rice, using a variety of water-cooked intact grains, such as quinoa, steel cut oats and farro, can help to reduce exposure. I agree that the use of brown rice in the diet should be limited or avoided. Because rice is grown in water-flooded conditions, it absorbs more arsenic than other plants. Arsenic is higher in brown rice than white, because it tends to concentrate in the outer layers of the grain. The FDA tested many varieties in 2012, and found a wide variation among U.S. grown brown rice. Brown rice grown in California had the lowest levels out of what was tested. Some companies test their own rice for arsenic and post the results online, and you can also view the FDA’s results online. Northern US, and Canada also produce wild rice, that is not commercially fertilized, and does not contain appreciable levels of arsenic.
What can all of us do to get more food packagers to put out purer foods? I'm referring in this question to the fact that so many products (such as raw nuts, and even many other raw packaged products like many from Navitas, as well as packaged dried beans) have notices on their labels that they were processed in facilities that also process wheat, dairy, soy, etc. I personally avoid those because I'm allergic to wheat, dairy and soy. When I ask what we can do (other than hope to find these products in purer forms), I mean, is there an organization fighting for purer products?
Unfortunately, it is difficult for smaller companies to package their foods without using plants that also package allergen-containing foods, and the final product must carry these labels as a safety precaution for those with severe allergies.
I was watching the Dr. Oz show one day when an expert mentioned that all canned goods are lined with a corn product. What do you think of that? I'm sure that corn product is not organic, and is therefore GMO. This is terrible for the many people who eat canned goods and are not aware of the GMO factor in the cans, no? What are your thoughts on this?
The most important concern about canned foods is the presence of BPA in the lining. I advise people to avoid canned foods as much as possible, especially tomatoes, since their acidity causes a higher level of BPA leaching compared to non-acidic foods like beans. You can buy tomatoes in glass jars or cook your own when they are in season and store them in the freezer; also it’s best to cook dry beans instead of buying canned beans. Studies show that carrageenan is harmful to human health. Some raw vegan restaurants use irish moss (a sea vegetable from which carrageenan is derived) in their recipes. I wrote to one of them (Quintessence Live in NYC) and the owners said they didn't believe the studies were valid. I did indeed write to an author of the carrageenan studies and she said irish moss is probably as harmful as carrageenan. What are your thoughts on this?
Irish moss is a seaweed and the source of carrageenan. There are still a lot of questions regarding the safety of carrageenan, and I recommend severely limiting the amount consumed. There is no human data studying the effects of carrageenan but there are numerous animal studies that show intestinal inflammation, ulcerations, and tumors when the animals were given a degraded form of carrageenan (not food-grade carrageenan). From the available science, it is likely that only the degraded form may be harmful, however there are concerns about possible contamination of food-grade carrageenan with degraded carrageenan, or that it may be degraded in the digestive tract. Until we know more about the health effects of this thickener on humans, I suggest purchasing products that do not contain it.
Why does the Nutritarian diet allow people to have any foods that come from animals? I know that 5% maximum is not much, but why include those foods at all?
Most of the studies about plant-centered diets have investigated near-vegetarian or near-vegan diets, and it is clear that reducing animal products in the diet in favor of whole plant foods reduces the risk of cancer, heart disease and other chronic diseases. There is some limited data, but no definitive data to suggest that a completely vegan diet is superior to one made predominantly of high-nutrient plant foods with a very limited amount of animal products. I am careful to report only what the science is suggesting rather than a pre-determined or favored opinion. I am attempting to advise people with the most lifespan enhancing information possible, state what is known and what we can logically assume from the information available and not let bias, personal preference or ego enter into my recommendations. My guess and experience is that some people will thrive better as a complete vegan and others may do better with a very small amount of animal products. I also want to accommodate those not willing to do a vegan diet, so they do not see it as an all-or-nothing choice.
What are your thoughts on recent studies done by Helen Vlassara finding that certain cooking methods (including frying, baking, roasting and grilling), produce harmful chemicals that cause aging and chronic disease?
It is true that cooking methods contribute to the disease risk associated with certain foods. We should avoid frying and also be careful not to overcook when baking and grilling. High-temperature, dry cooking produces potentially carcinogenic compounds– acrylamide (formed in starchy foods) and heterocyclic amines (formed in meats). Toxins called advanced glycation end products (AGEs) are formed in both animal foods and carbohydrate foods. AGEs contribute to the oxidative stress and inflammation characteristic of diabetes and its complications, Alzheimer’s disease, and cardiovascular disease. AGEs may be formed during cooking and also in the body after the foods are eaten. Some examples of fried and overcooked foods high in these toxins are processed meats, blackened grilled foods, potato chips, French fries, baked goods and sugar-coated breakfast cereals. We should avoid these foods, and use conservative cooking methods such as wokking, water sautéing, and making soups and stews to limit the formation of these toxic compounds.
Is it true that vegans are not getting enough DHA?
The primary dietary source of DHA and EPA, of course, is fish. The precursor to DHA and EPA, ALA, is available in plant foods such as chia seeds, flaxseeds, hemp seeds and walnuts. The body needs to convert ALA into DHA and EPA, but it only has a limited capacity to do so. Conversion efficiency is generally low and varies greatly between individuals. Also, a substantial amount of the ALA we obtain from our diet is burned for energy, rather than converted to EPA and DHA. Therefore, it is possible even for those eating an ideal high-nutrient diet to have suboptimal levels of DHA and EPA. In fact, a recent study on omega-3 levels in vegans who didn’t take supplements found that 64 percent had low levels, and a smaller percentage had severe deficiencies.
DHA and EPA are crucial components of human brain tissue, and inadequate DHA and EPA later in life is an important concern because of an increased risk of brain shrinkage. Low DHA index in the blood has been linked to later life brain shrinkage, Alzheimer’s and cognitive decline. Maintaining brain health with age is a significant concern, especially if we plan to live significantly longer than the average American, so we should ensure that we are getting enough of these brain-healthy fats. My 25 years of experience as a primary-care physician treating this community has confirmed these risks.
It is irresponsible to assume that everyone will convert enough ALA into DHA to protect your brain later in life. Either check your omega-3 fatty acid levels with a blood test to assure that you are sufficient, or take a low-dose algae-derived DHA + EPA supplement, or both.
Joel Fuhrman, M.D., is a family physician, New York Times best-selling author and nutritional researcher who specializes in preventing and reversing disease through nutritional and natural methods. Dr. Fuhrman is an internationally recognized expert on nutrition and natural healing, and has appeared on hundreds of radio and television shows including The Dr. Oz Show, The Today Show, Good Morning America, and Live with Kelly. Dr. Fuhrman’s own hugely successful PBS television shows, 3 Steps to Incredible Health and Dr. Fuhrman’s Immunity Solution bring nutritional science to homes all across America.