Nutrition is a complex topic. The process of digestion is one of the most fascinating and least understood functions of the body. Food is also a very social activity, rooted in history and culture, which means everyone has different ideas about it. Over the years, I’ve experimented with many different diets, including sprouted and fermented foods, raw foods, local, in-season foods, and macrobiotic foods. Though the differences may appear confusing at first, when each one claims to be the key to health, they all share certain guiding principles.
Rather than learning the ins and outs of the latest fad diet, we need to understand basically why food is a source of energy and how it can support our health. A friend of mine once said “if you can’t explain your idea to a six year old, you don’t really understand it yourself.” The six-year-old test is a good measure of whether or not your ideas are grounded in common sense, or whether they’ve gone flying off into Interesting Hypothesis land. Here are a few principles of healthy eating that I’ve gathered over the years, with my attempts to translate them into six-year-oldese.
- Nutrition represents the activities of many different foods working together. The whole is greater than the sum of its parts.
Translation: Nutrients are the parts of food that make us healthy. Each food has lots of different nutrients. Some nutrients get along really well, like friends. When they work together, they make something a lot more complicated and beautiful than they would all by themselves.
- Vitamin supplements don’t make up for a poor diet.
Translation: When you take one nutrient away from all the other nutrients, it can’t always work the same way it did before. It might stop working, or it might do something you don’t want it to. Eating whole foods like bananas, taro, papayas, avocadoes, rice, sweet potatoes and whole wheat pasta is better for you than eating junk food and taking vitamin supplements.
- A well-balanced plant-based diet can give us all the nutrients we need to thrive and help us avoid many diet-related diseases.
Translation: Animals have different nutrients in their bodies than plants do. Animals have a lot of cholesterol and fat in their bodies, which helps them stay warm and gives them energy. When we eat animals, all that cholesterol and fat goes in our body, and it can clog up our hearts and arteries. Plants have lots of fiber which helps them grow tall and other vitamins and minerals that they get from soaking up water, sun and soil. When we eat plants, all the fiber passes through our body and helps our digestion, and all the vitamins and minerals help our bodies grow and fight off sickness. 
- Good nutrition creates health in all areas of our existence. All parts are interconnected.
Translation: Sometimes, when your body’s sick, your mind starts to feel sick too. It’s hard to be happy and think clearly when you have aches and pains everywhere. If you keep your body healthy by eating a well-rounded plant-based diet, your mind will be healthier and the planet will be healthier, too. Growing plants takes a lot less water, land and oil than raising animals. If we keep the planet healthy, we will have more space to play outside, which makes us feel happier and keeps our bodies healthy.
If anyone has a six-year-old in the house (or anyone who isn’t familiar with nutrition), try to explain these principles of a whole-foods, plant-based diet to them. I’d love to hear your translations and your results!
 For those who maintain a plant-based diet for more than three years, a vitamin B12 supplement may be necessary. Studies have shown that vitamin B12 is available in plants grown in organic soil with a healthy microorganism population (Mozafar A. "Enrichment of some B-vitamins in plants with application of organic fertilizers." Plant and Soil 167 (1994): 305-311). But since most crops in the United States are grown in lifeless soil, vitamin B12 is not readily available. Nutritional yeast and blue-green algae are good sources of vitamin B12 and are also tasty additions to soups, salads, vegetables and grain dishes.