The biggest problem I find in eating a primarily plant-based diet (aside from the unfortunate problem of many of my carnivorous friends and associates making ignorant, unprovoked comments as they shove flesh in their faces -- you know who you are) is that many of the items meant to replace meat are primarily made of soy. This is problematic for me for three reasons: 1) I think tofu is sub-par in consistency and taste, and really has no place in my culinary lifestyle as a result; 2) I have several food sensitivities (which most of us do, although usually undiagnosed-- which I will also address in later blogs, don't you worry friends), one of which is to Soybeans; 3) Despite its potential benefits, which are unfortunately usually overestimated, Soy has many negative properties on both our health and our world, all of which I am hoping to present to you in this blog so that you too can make an educated decision on what you put into your body. I would like to preface this information by stating that no matter what negative effects soy may have on your body, as a whole if the choice is between a soy-based product (at appropriate serving sizes) or an animal based product, soy is usually the better choice in terms of cholesterol, embedded toxins, and saturated fat. Therefore, when you hear that vegetarians who eat soy as a major source of protein are healthier than those who eat animal products, you are hearing correctly. I would also encourage anyone who is choosing soy due to a sensitivity to dairy (casein or lactose) to be tested for a soy allergy also, as soy allergies are equally if not more common than dairy-based allergies and should not be taken lightly due to potential long-term effects (this es-pec-i-a-lly applies to soy-based formulas for babies who are sensitive to dairy -- make no dietary changes of this sort without a documented allergy test! Until you obtain one, use amino-acid based hypo-allergenic formulas such as Neocate).
So here goes...
Important things to consider about soy before consuming it in any amount:
1. Not all soy is alike. Processing methods and quality can make a HUGE difference on the ability to process soy by the body and on the potential harmful effects of consuming these products. For example, Asians are often viewed as prime examples of benefiting from a primarily soy-based diet, as they have a much lower incidence of breast and prostate cancer which many studies have credited to their soy consumption. However, the type of soy they usually ingest (on average about 9grams per day) is fermented soy -- found in miso, tempeh, natto, and some tofu-- which creates health-promoting probiotics, the good bacteria our bodies need to maintain digestive and overall wellness. By contrast, most American-made soy containing foods contain processed soy which can contain over 20 grams of nonfermented soy protein in one serving. Remember, soy is not a food that is originally native to North America or Europe, and many times this causes a disturbance in the general population's ability to digest it and/or process it appropriately. This is similar to the problem of lactose intolerance in Asia, as cow's milk is not a commonly used product in Asian countries and therefore their population has not developed the bio-mechanisms to properly digest casein (milk protein) and lactose (milk enzyme). Think about it, have you ever heard the phrase, "would you like some cheddar on your ahi tuna?"
2. Soy is an e-nor-mous $$$$ maker in this country and others. These days the industry has discovered ways to use every part of the bean for profit. Soy oil has become the base for most vegetable oils; soy lecithin, the waste product left over after the soybean is processed, is used as an emulsifier; soy flour appears in baked and packaged goods; different forms of processed soy protein are added to everything from animal feed to muscle-building protein powders. Therefore, nearly every study that has come out addressing the concerning effects of soy has been rebutted by another study by the soy companies promoting the good effects of consuming the product. "Soy protein isolate", which I bet you'll find in many of your packaged foods now that you will be looking, was approved for use in cardboard -- and still to this day has not been approved as a food additive. Ew. Soy is everywhere in our food supply, as the star in cereals and health-promoting foods and hidden in processed foods. Even if you read every label and avoid cardboard boxes, you are likely to find soy in your supplements and vitamins (look out for vitamin E derived from soy oil), in foods such as canned tuna, soups, sauces, breads, meats (injected under poultry skin), and chocolate, and in pet food and body-care products. It hides in tofu dogs under aliases such as textured vegetable protein, hydrolyzed vegetable protein, and lecithin--which is troubling, since the processing required to hydrolyze soy protein into vegetable protein produces excitotoxins such as glutamate (think MSG) and aspartate (a component of aspartame), which cause brain-cell death. Bottom line, you are consuming generally more soy than you think, so it is important to remember that when intentionally consuming soy products in addition to these sources.
3. Soy contains phytoestrogens and isoflavones, which act as a precursor to estrogen in the body. This is whether you are a male or female, transgender or michael jackson, menopausal or an infant -- everyone can absorb these hormone-like substances and everyone can be affected by them. Studies on the effects of isoflavones on human estrogen levels are conflicting, and it's possible that they affect people differently. For some people, such as menopausal women, the ingestion of soy can help symptoms of estrogen deficiency such as night sweats, hot flashes, and mood swings. But before you trick mom into eating soybeans to give your ear a rest, remember that these same properties also have the potential to promote hormone-sensitive cancers in all people. Some studies have shown soy to lower testosterone levels in men and to decrease libido. Anecdotal stories of friends and patients of mine who have switched to soy milk or other soy-based products seem to consistently have a few themes including developing breast tenderness, mood swings, and menstrual dysregularities. If you are concerned, you can obtain estrogen-like properties from lima beans or flax seeds instead.
4. Soy-based infant formulas are highly controversial, and the data is conflictual at best. Some have gone so far as to call infant formulas "baby birth control" due to the potential for hormone imbalances in infants who are fed soy formulas. The problem here is that the formulas are their main source of nutrition for many months, and that they are at a key stage of development during this time period. The estrogen in soy will affect the hormonal development of these children, with the potential to affect their growing brains, reproductive systems, and thyroids at unknown levels. Soy formula also contains large amounts of manganese, which has been linked to attention deficit disorder and neurotoxicity in infants. The Israeli health ministry recently issued an advisory stating that infants should avoid soy formula altogether. So far the US is yet to issue any sort of recommendation. Personally, I would prefer an amino-acid based infant formula (if you must use formula as opposed to breast feeding, which is always best for the first year of life) such as Neocate to provide complete nutrition with almost no chance of stimulating or inducing a food allergy during these early crucial months. That being said, if an infant has shown no GI distress after ingesting soy it is most likely a better alternative than cows milk, which is one of the most difficult proteins for humans (not just babies) to digest... but this is a topic I wont even get started on...
5. In 2000, the Nutrition Committee of the American Heart Association published a major statement in the peer-reviewed journal Circulation, officially recommending the inclusion of 25 grams or more of soy protein, with its associated phytochemicals intact (i.e., not in the form of an isolated soy protein supplement), in the daily diet as a means of promoting heart health. This recommendation is consistent with the FDA's recent ruling allowing soy protein products to carry the health claim: "25 grams/day of soy protein, as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease." Soy consumption tends to bring down total cholesterol levels most in people whose cholesterol levels are high. But even people with normal levels benefit from eating more soy, according to dozens of studies, because it improves the ratio between HDL (good) and LDL (bad) cholesterol. This ratio is now recognized by the American Heart Association to be an even more important factor than total cholesterol levels in heart disease risk.
My recommendations:
- Because of these potentially good effects, I personally would recommend consuming between 20-25 grams of soy protein per day (if any), but not exceeding this dosage in order to avoid more hormone-related side effects discussed in the former note. If you are lucky enough to have the choice, always choose fermented soy products vs. processed soy products to gain full benefits associated and to better avoid risk factors associated with eating soy. If you begin to have headaches, menstrual irregularities, or mood swings, consider limiting your soy consumption to see if this helps. If you have GI symptoms such as constipation, diarrhea, bloating, or irregularity (<1bm per day), try eliminating one food at a time (soy, again, is a common food intolerance) for 2-3 weeks to see if you feel better. Your practitioner can order certain lab tests which clarify food intolerance, but food elimination challenges are always best.
- As John Robbins says, "Soy supplements are a different story. Soy pills and powders can contain amounts of isoflavones (usually daidzein and genistein) far in excess of the amounts possible to get through diet. Very little research has been done on the effects of such mega-doses. Although there is no firm evidence to demonstrate that ingestion of isoflavones has adverse effects on human beings, there is also no clear evidence that large doses are safe. When manufacturers of soy protein isolates and supplements recommend that people consume 100 grams of soy protein a day (the equivalent of 7 or 8 soyburgers), they are ignoring the unknown effects of overdosing on isoflavones. I believe it's probably safer, until more is learned, to avoid concentrated soy supplements entirely."
- Some studies show that soy contains "anti-" nutrients that can actually hinder the body's absorption of certain vitamins and minerals. Because everyone's GI tract is different, and it is unknown how much soy consumption would actually be harmful in terms of mineral absorption, just be sure that no matter who you are or what your diet is that you take a multi-vitamin daily that contains the daily value (at least) of zinc, vitamins a-d, magnesium and calcium (have to be taken together for best absorption), and omega-3 fatty acids (liquids are best, but if you prefer pills get refrigerated ones from healthfood stores that are known to be as pure as possible and not made from rancid fish sources).
- The more variety in your diet, the better. Stick with whole grains, vegetables, fruits, and (if you choose to eat animal products) try to get organic meats that are hormone-free, antibiotic free, and lean cuts. The more organic you can consume, the better off you will be. If the cost gets you down, just remember the most important things to buy organic are those that have an outer skin that will be consumed (for example, organic bananas are not as important bc you remove the skin, while apples, zucchini, and cherries are quite the opposite).
Common sources of soy:
Tofu
Soy milk, curdled and pressed into cubes of varying firmness. Often used as meat substitute. A nonfermented product, tofu contains antinutrients, which can block absorption of essential minerals.
Miso
Fermented soybean paste, used in soups and sauces. Rich in probiotics, good bacteria that aid vitamin absorption. Miso is high in sodium but is considered one of the healthiest soy products.
Soybean Oil
To extract oil, soybeans are superheated, ground, pressed, mixed with chemicals, and washed in a centrifuge. Soybean oil accounts for 80 percent of all liquid oils consumed annually in the United States.
Soy Milk
A processed beverage made of ground soybeans mixed with water and boiled, which removes some toxins. Sugar is added to improve flavor. An eight-ounce serving contains up to 35 milligrams of isoflavones, which may change estrogen levels and hormonal function.
Snack Food
Highly processed, a source of trans fat. Check your labels: Potato chips, tortilla crisps, and many other deep-fried things have been cooked in soy oil--straight up or partially hydrogenated.
Tempeh
Whole soybeans pressed into loaves, which are then fermented. Often used as a meat substitute. Tempeh is rich in B vitamins, minerals, and omega-3 fatty acids.
Fast Food
A source of hidden soy. Processed soy proteins extend some burgers and chicken (nuggets, patties, even 'grilled breasts'). Buns contain soy oil and to a lesser extent soy flour and lecithin. Soy oil also appears in dressings and dips, in American 'cheese,' and as the No. 2 ingredient in fries. There's even soy in Big Mac's secret sauce: Soybean oil nets top billing.
Edamame
Whole soybeans, commonly boiled in the pod and eaten as a snack. Most commercial edamame has been preheated to make digestion easier, but it still contains antinutrients.
So(y) long for now...
No comments:
Post a Comment