Our hunter & gatherer ancestors ate a diet of fresh and organic foods and did not have as many options for "empty calories" as we do. The folks at the Weston Price Foundation regularly talk about the importance of eating "nutrient dense" foods. Its an important concept to keep in mind: It is a worthy goal to make sure everything you eat is packed full of vitamins, minerals and all manner of good nutrition.
Here are some guidelines for including more nutrient dense foods in your diet:
Avoid buying foods that are already cut, peeled and diced at the store. Nutrients can break down the longer they are exposed to the air.
Avoid peeling foods at all! Buy a vegetable brush instead of a peeler. Mashed potatoes with bits of skin in? That's the best! The peels are often where the most nutrition is, anyway. The problem is that skins are also the place most likely to contain pesticides. Buying organic helps to deal with that problem (its not foolproof, since some organics can have cross-contamination from other fields (even though that's supposed to invalidate their "organic" status), or it could have gotten contamination in the picking and shipping--just wash them). You can buy solutions that will clean the wax and other chemicals off of fruit before buying them, as well.
Eat foods that spend the least amount of time between harvest and your table. Sometimes canned and frozen foods are really good in this regard: They are often preserved within hours of harvesting, whereas "fresh" foods at the grocery store may have been picked days or even weeks earlier. Its important to eat some raw foods, though, so there is a place for those fresh items in your diet. However, a better option is buying food that was picked just hours ago (from a local farmers market) but still fresh. A step further, eating veggies or berries right off the plants in your backyard garden while standing in the noonday sun is, as they say, priceless.
Know where your food has come from! The nutrition of food is highly dependent on the soil and agricultural techniques of the farmers. This goes for animals, too. Animals raised on natural diets are much more nutritious than the factory farmed ones (cows eat grass, not grains!) Many of the organic eggs around here boast having 30% higher levels of Vitamins A and E and some minerals, too, than the non-organic varieties. You don't need to know the nitty gritty of all farming techniques. Just knowing that the farmers regularly build up their fields with natural compost instead of oil-based fertilizers and raise their animals on a diet that is natural to the animal will be enough. Factory farms have been depleting their soil for generations, which results in poorer quality foods.
When in doubt, err on the side of organics. You can taste the nutrition. If a carrot is positively bursting with flavor, odds are it is bursting with nutrition, too.
Eat whole grains. A common guideline is that 50% of your grains should be whole. Our culture makes them scarce in restaurants and common recipes, but the whole grains are out there if you know where to look. You just gotta learn how to start slowly incorporating them into your regular routine. It took me a while to phase them into my diet, as well, but I learned some recipes and found good places to shop. Once you get accustomed to them, they are often much more flavorful than the alternative and you may just prefer them. Experiment around.
If your whole-wheat bread is hard and dry, its not being prepared right. Whole grains can be (almost) every bit as light and fluffy as white breads, but you need to find a baker who knows what they are doing.
See the accompanying chart on the left which compares the nutrient content of whole vs. refined grains.
"Enriched" grains add three different B vitamins and iron (more than what was originally present in the grain), but take a look at all of the other nutrients that are not being replaced!
You can view this chart as half-full or half-empty. It is kind of reassuring that even refined grains retain some of the nutrition of whole grains--they are not stripped completely bare. However, the refined grains contain less than 25% of what they started out with on a number of important nutrients. It may not be enough.
Do you really want to eat food where 2/3 of the nutrients have been stripped out, with a few of them artificially replaced back in?
The good news is that you get a lot from whole grains, more than just a few B vitamins and fiber.
I wonder if there are any reasons not to make 100% of your grains whole? I can only think of one reason: People who are just beginning to incorporate whole grains and other fiber-rich foods into their diet should do so slowly. It can be a shock to your system if you are not used to it, and your body will need time to adapt. However, I am fully used to it, and still wonder if there is any reason to hold back on whole grains? I need to research more on this. Just living in America, its hard to avoid refined grains entirely, but I've been able to do it pretty well for extended periods.
Consider how your food is cooked. You can take a beautiful, vitamin rich vegetable and reduce it to a hunk of empty starch if you don't know what you are doing. That's what happens when you make french fries. Potatoes have enough nutrition to sustain entire cultures of people almost entirely on that single crop. But the minute you peel it and throw it into a deep fryer, you end up with a batch of starch + assorted carcinogens. Nutrients have either been washed out, incinerated or thrown away with the peels.
Slow cooking is one of the best ways to preserve nutrition. I rarely have my range jets higher than 40%, and quite often I use the lowest flicker of a flame possible. High heat is only for bringing something to a boil or prepping a pan before food gets tossed in. Sometimes a lower flame only adds another 5-10 minutes to cooking (depending on what you're making), and it is well worth it. Crock pots, anybody?
Try whole sugar, honey or maple syrup instead of bleached and stripped white sugar.
At every chance you can get, eat whole foods. Keep the peels on, keep the grains whole, eat the pulp. Our bodies have evolved to eat them. And don't be afraid of eating the whole animal, for you meat eaters. Organs, skin and bone-in dishes provide vital nutrition that is sorely lacking in our culture.
The good news is that if you follow these guidelines, you can eat basically the same amount of food you currently eat. You are increasing the nutrition without increasing the calories. That's what it means to be nutrient dense.
Vitamin pills or foods injected with vitamins and minerals may not always give the return you are hoping for. Antioxidants in particular have not been very unsuccessful in supplement form. Old standbys such as iodized salt are still a good choice, though. I don't take any pill supplements, although there are probably really good ones out there. Much of the "good stuff" in food cannot be reduced to a simple amount of vitamins. This is why there is such a buzz about "whole foods" lately. When food is stripped of its wholeness, often what is lost are the proper pathways and support structures that deliver those nutrients to your body. This is a hypothesis as to why antioxidants do not work when taken in pill form. The antioxidant lycopene has been shown to provide all sorts of benefits, but lycopene pills do not seem to have much of an impact at all, compared to people who simply eat a lot of tomatoes.
Its scary to watch my parents skin the meats, cut off the fat, peel potatoes and carrots, make gravy from a powder rather than the meat juices right in the pan. Maybe they intuitively know something that I don't know, but so far the research seems to indicate that preserving the wholeness of foods is the way to go. There is a place for juice without pulp and non-whole grains, but those should be exceptions, not the rule.
Everything you eat can and should be packed with natural vitamins and minerals. It is not always a bad thing to eat empty calories. But every time you eat that white bread, think about what you could have eaten. Americans are well-fed, but often starving themselves of important nutrition, because the foods they eat are plentiful in volume but sorely lacking in quality. Every time you eat your empty calories you are hurting yourself not because of what you eat (although that factors in, too), but because of what you could have eaten, instead.