Foodist Page 6

  Your metabolism starts responding simply to the smell of food.* How quickly you eat and how much you chew also impact how your body handles it. Your own genetic makeup as well as your fitness level dictate how you respond to different levels and combinations of nutrients, and your digestive tract contains trillions* of microorganisms that affect what you can and cannot absorb. Individuals vary greatly in their sensitivity to different micro and macro nutrients, and all of us have different personal health and fitness goals.

  One reason it is difficult to give nutrition advice is that there is no formula that will work for everybody in all situations. Moreover, we don’t understand the details of most of these processes well enough to give reliable answers. Since we don’t know far more than we do know, you should be skeptical of anyone claiming to have all the answers. Personally, I do my best to keep up on the science, but always with the understanding that we are several decades (possibly even centuries) away from even pretending to be able to prescribe an optimal diet for every individual, if such a thing even exists (it probably doesn’t). Yet despite our gaps in understanding, we have seen that humans are incredibly adaptable to different diets and can thrive in a multitude of environments.1 So part of what defines the best diet for you will be what your circumstances allow for. Within that framework you’ll have to do some guesswork, starting with the best information you have and then experimenting on yourself to see what works.

  THE THINGS WE KNOW

  The situation may sound grim, but there’s no need to join a suicidal space cult just yet. Even without knowing the exact details of how the homofermentative metabolism of Lactobacillus in the human intestine impacts blood glucose, we still know enough about certain groups of foods to give us a decent idea of what does and does not constitute a healthy diet. It is also much easier to talk about whole foods (you know, those things we actually eat) than it is to discuss the individual nutrients that may or may not behave the way we expect them to once they’ve been eaten. Let’s start with a few nutrition facts that virtually all scientists, nutritionists, and diet camps agree upon.

  VEGETABLES ARE GOOD FOR YOU

  Everyone agrees vegetables are good for you. Eating more vegetables is linked to lower body mass index (BMI) and less risk for heart disease, stroke, high blood pressure, cancer, diabetes, and pretty much every other diet-related disorder under the sun. Though we do not know the exact reasons why,* vegetables seem to protect us from a lot of the other bad things we do to ourselves. And though I’ve heard a few extremists argue that vegetables aren’t as necessary as everyone claims,* it’s a safe bet that vegetables do more good than harm.

  REFINED STARCHES AND SUGARS ARE BAD FOR YOU

  The nutrition community is one of the most disagreeable bunches in all of science. To hear the diet fundamentalists argue, you might think we were on the brink of a holy war. But across the board, from vegans like Dr. Colin Campbell to carnivores like Dr. Robert Atkins, not one of them considers refined carbohydrates to be nutritionally neutral—they all consider them dangerous. Take it to heart, because we may never see this kind of civility again.

  Because they are processed, refined carbohydrates are not technically whole foods, but most of us recognize them as a class of foods that includes breads, cakes, chips, sweeteners, and sodas. Their hallmark ingredients are refined flour and sugar, and it’s appropriate to call this stuff junk food. You’ll see that you can still save some space for them in your healthstyle, but under no circumstances should you forget that these are not health foods.

  THE SUPERFOOD ILLUSION (AKA THE FINE PRINT)

  Before we move on to the more controversial foods, I want to pause and reflect on what we’ve covered, lest we become too dogmatic and overconfident about what we actually know. I’ve said it’s undeniable that vegetables are healthy, but that doesn’t mean you should start eating celery like a health-crazed lunatic. Remember that the details of why these foods are good for us are still relatively unknown, so it’s important not to fall into the “superfood illusion” and gorge yourself on a handful of select foods just because of some wonder nutrient they are supposed to possess.

  I always cringe when I hear a scientist use the word “superfood,” because I know it will inevitably be parroted by the media or, worse, a food company trying to sell us some bogus product. “Superfood” is a marketing term typically used to mean a plant (e.g., blueberries) or animal (e.g., salmon) that contains high levels of a particular nutrient (antioxidants! omega-3s!) that can supposedly help with a certain health issue. When something gets labeled as a superfood, most of us automatically assume it is extra super-duper healthy and we should go out of our way to eat more of it. Not that we will (according to decades of research, few people can even manage five fruits and vegetables a day), but maybe we’ll try to try and eat more.

  To their credit, the superfood lists I’ve seen usually contain legit health foods. They tend to be fruits, vegetables, fish, and other natural ingredients. Thankfully, I haven’t seen any reports that bottled vitamin water is a superfood and actually good for you. But it is naive to believe there is some list of magical foods that will save you from certain death. Obviously nutrients are important (and vitamins are essential), but large doses of them from either food or supplements are almost never associated with benefits beyond what you can expect from having an overall healthy diet. This is because the way our body deals with micronutrients is not linear (i.e., more does not mean better). Instead, there is typically an ideal dose range for a given nutrient; amounts below or above this range are both bad, but any reasonable quantity in between is pretty darn good. Think of Goldilocks finding the perfect porridge temperature and bed softness. In normal ranges your nutrient levels will be just right, freeing you to go about snooping in the homes of bears (or whatever).

  Though it is hard to overdose on whole foods, it is possible. In 2010, the New England Journal of Medicine reported that an eighty-eight-year-old woman fell into a coma after eating 2 to 3 pounds of raw bok choy each day for several months.2 She had been attempting to control her diabetes, but instead induced a state of severe hypothyroidism. Though bok choy is typically a very healthy vegetable, when eaten raw and in large quantities some of the compounds in it break down into chemicals that inhibit the thyroid. The lesson here is that bingeing on random foods (even if you convince yourself they’re healthy) isn’t a good idea. But more important, eating a lot of one kind of food almost certainly won’t give you any health advantage. If you’re eating one thing, that means you aren’t eating something else, and in Western cultures what we’re really lacking is nutrient diversity.

  The Top 10 Most Overrated Health Foods

  Like it or not, we tend to believe whatever we are exposed to in the media and in advertisements. In nutrition this usually means that as a society we all follow the same diet fads, glorifying some foods over others in the quest for better health. (It’s okay. I love salmon and coconut water as much as you do.)

  The problem is, though, that more often than not the news or the health claims made by food manufacturers vastly overstate any potential health benefits, because doing so makes a more compelling story and sells more products. Our own confirmation biases tend to make us believe what we’re told, we confidently share our insights with our friends, and suddenly our grocery stores are filled with health foods that really aren’t all they are cracked up to be. Here are my ten picks for the most overrated health foods.

  1. Yogurt

  There is nothing innately wrong with yogurt, the natural product. But the real stuff is not nearly as easy to find as the hypersweetened dessert versions filling supermarket shelves. Though yogurt can contain beneficial probiotics, friendly bacteria are also present in other fermented foods like sauerkraut, kimchi, and miso. And if you are worried about acne, dairy is probably not your best choice. Oh, and the overratedness is doubly true of frozen yogurt.

  If you’d rather keep yogurt as your breakfast staple (something I often use myself
), go for plain yogurt, preferably full fat. Don’t fall for the vanilla trap; it is not plain and has even more sugar than most fruit versions.

  2. Soy

  Soy is another one of those foods that can be perfectly healthy, but can also be processed into oblivion, making it an unhealthy product. Hydrogenated soy oil is among the most common sources of trans fat. Processed products are often touted as healthy just because they contain soy, but soy is not exactly the health panacea it is often made out to be. For a healthier version, stick to fermented soy products like miso, natto, or tempeh.

  3. Egg Whites

  It baffles me that Americans continue to vilify the most nutritious part of the egg while glorifying the less impressive half. Sure, egg whites are a good source of protein on their own, but you’re probably not lacking protein and would likely benefit from the rich nutrients of the entire egg.

  4. Margarine

  Why we need artificial processed oils when there are so many naturally healthy sources of fat is beyond me—that is, assuming you can even find margarines that do not contain hydrogenated oils (trans fats). If you really want more stanols and sterols in your diet, try eating more nuts, avocados, and vegetables. If you want to add buttery flavor, just use real butter (preferably from grass-fed cows).

  5. Bananas

  I have a bit of a reputation for picking on bananas, but I really don’t think they’re all bad, and they definitely taste yummy. My biggest problems with them are that they are produced industrially and are one of the most calorie-dense fruits you can buy. When is the last time you saw a banana at the farmers market anyway?

  Bad for you? Not really.

  Overrated? Definitely.

  6. Fake Meat

  Next time you get a chance, check out the ingredients in your favorite meat substitute. It usually contains a lot of gluten, some processed soy, canola oil, cornstarch, and a few bizarre ingredients like “natural vegetarian flavors” (mmm . . . vegetarians). Call me crazy, but real meat sounds a lot more appealing.

  7. Protein Bars

  Remember back in the day when protein bars tasted like crap? Well, they would all still taste that way if manufacturers didn’t fill them with sugar or sugar substitutes. Look at the ingredients. The vast majority of protein bars contain the same processed junk that’s in everything else, just with a few more vitamins, some added soy protein, and possibly some added fiber. Adding nutrients to junk food does not a health food make.

  8. Whole-Grain Flour

  Ah, whole grains, how controversial be thy name. Though I’m not as antigrain as some folks, I don’t pretend that highly processed “whole-wheat flour” is actually good for me. Grains that don’t look like grains are not your friends.

  9. Low-Fat Salad Dressing

  Fat is good for you. Yes, fat contains more calories than protein or carbohydrates, but it also enables you to absorb more vitamins from the foods you eat and makes your meals more satisfying. Fat-free dressings do not make you healthier; they make your salad less nourishing.

  10. Fruit Juice

  Juicing fruit concentrates the sugar while stripping out the filling fiber. When you remember that one 450-ml (15-ounce) bottle of orange juice is equivalent to six whole oranges, you can start to see the problem. Green juices are fine; just be careful with fruit juices.

  The vast majority of our diets are made up of the same handful of foods that we eat over and over again. Even people who make sincere efforts to eat healthy have rather limited diets. Broccoli, carrots, and zucchini are great and all, but it pays to be a little more creative. Throwing blueberries in there every now and then can only add so much. There are hundreds, maybe thousands of important nutrients (vitamins, antioxidants, phytochemicals, etc.) that our bodies need for optimal performance, and as we discussed earlier we probably don’t know what all of them are, let alone what functions they serve. Every natural food contributes its own unique blend of nutrients, so if you want to get the most from your diet, you’re much better off focusing on dietary diversity rather than loading up on the top ten foods some magazine says you should eat more of.

  All that said, it does make me happy when lowly, forgotten vegetables like beets and lima beans get featured in the New York Times. Vegetables need all the press they can get, and it’s true that most people don’t eat enough vegetables, period. Any article that encourages you to try a new kind of food is a good thing. But keep in mind that if you see a food labeled “super,” you should take it with a grain of salt, because when it comes down to it all natural foods are superfoods. The ones that make the news just happen to be those that some scientist or reporter decided to shine the spotlight on for the time being.

  SEAFOOD IS GOOD FOR YOU (USUALLY)

  Seafood marks the beginning of the healthy-eating gray area. If we had pristine rivers, lakes, and oceans, there wouldn’t be much of an issue. Where the science stands today, the evidence is pretty convincing that fish and seafood, when unadulterated, are uniquely healthy. The problem arises when we consider the environmental toxins that pollute our waterways and contaminate our food as well as the ecological issues caused by overfishing. I’ll address these issues separately in the following pages.

  Though I prefer not to focus on individual nutrients, it is clear that seafood is rich in at least two essential omega-3 fatty acids, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), which are virtually impossible to get from other sources.* These are essential fatty acids, meaning that, like any other vitamin, you should consider them necessary for your body to function properly. Fish oils protect against heart disease and help preserve cognitive function during aging. They also help fight depression and rheumatoid arthritis and are essential for proper brain development in children. These fatty acids also have anti-inflammatory properties and have been linked with healthier digestion. With two or three servings of oily fish per week* all of these benefits could be yours.

  Fishing for Answers: How to Choose Fish and Seafood

  I don’t think there is anything more complicated in the food world than fish and seafood. There are so many life-or-death issues, it’s enough to make you want to cover your eyes, plug your ears, and live out the rest of your life in a cave on Mars. But this isn’t really one of those issues we can ignore. Beyond the obvious health benefits of seafood, we must consider the consequences of environmental contaminants that accumulate in fish as well as the tragic reality of overfishing and the damage the fishing industry is doing to the environment.

  Mercury

  Mercury is released into the environment by chlorine plants and coal-fired power plants. Once released from a power plant, mercury settles in nearby aquatic environments, and bacteria there convert it into methylmercury. Residing at the base of the food chain, these bacteria are consumed by plankton, which are then eaten by smaller fish, which are in turn eaten by larger fish. Methylmercury has a seventy-two-day half-life, so it accumulates in animals highest on the food chain. The larger the fish, the more the methylmercury contamination. Predatory fish such as tuna, shark, swordfish, tilefish, and king mackerel have high methylmercury levels. As predatory consumers of large fish, humans are also subject to methylmercury accumulation.

  The FDA warns against mercury exposure, particularly for women who are pregnant, may become pregnant, or are nursing, and children under the age of six. Methylmercury is a known neurotoxin that is able to cross the blood–brain barrier into the central nervous system and placenta. It can be dangerous for anyone exposed to high concentrations, but is particularly dangerous to children whose nervous systems are still developing. The FDA recommends that fish with high mercury content be consumed no more than once a month for normal adults and completely avoided by children and pregnant women.

  For most fish consumers, tuna is the biggest concern. Bluefin, bigeye, and albacore (white) tuna contain the highest methylmercury levels. Albacore is sometimes canned, but the most common canned tuna in the United States are yellowfin and skipjack tuna. Skipjack tun
a, being a much smaller fish, is relatively low in methylmercury compared to other options. It is usually labeled “chunk light tuna,” but you need to read the label carefully to see that it is not yellowfin or albacore.

  PCBs

  Farmed fish tend to be lower in mercury concentrations, but much higher in polychlorinated biphenyls (PCBs). PCBs are chemical contaminants known to cause problems with cognition, reproduction, development, and liver function and can promote endocrine disruption. They are also thought to be carcinogenic. Though their industrial use was banned back in the 1970s, PCB contamination is widespread in American waterways and throughout the world. PCBs pose a problem because virtually all fish have some contamination, but farmed fish, particularly those fed fish meal and fish oils, tend to have more. Farmed fish are also usually less nutritious due to their limited diets. Did you know that all farmed salmon is dyed pink, because naturally it appears gray and unappetizing? Eeeew.

  Basic Guidelines

  For health, the basic guidelines I recommend include:

  • Eat fish two or three times a week.

  • Avoid large fish that accumulate mercury like tuna, shark, and swordfish.

  • Avoid farmed fish that contain PCBs.

  • Seek smaller fatty fish such as salmon, mackerel, and sardines.

  • Avoid freshwater fish caught by friends. Almost all lakes and rivers are contaminated with high mercury levels.