On closer inspection it appears that the authors of all of the above-mentioned books recommend eating lots of vegetables and not a lot of sweets and other junk foods. Indeed, I’m tempted to conclude that just one broadly defined healthy diet will allow me to achieve all of my health objectives! (Agnostic healthy eating, anyone?) Okay, I’ve removed my tongue from my cheek. The point of the forgoing exercise, as you may have guessed, was to highlight the absurdity of eating for single, specific objectives. The body is an integrated whole. A person has only one diet, and it affects every dimension of health simultaneously. What’s more, precisely because the body is an integrated whole, any food type that enhances one dimension of health is likely to enhance others and is unlikely to have a negative impact on any.
Take whole grains, for example. Consumption of whole grains has been shown to favorably impact gut health and to reduce insulin resistance and systemic inflammation as well as the risk for several cancer types and heart disease. Vegetables and fruits likewise boost all dimensions of human health while nuts and seeds have a wide range of healthful effects and no negative effects. Fish too has a handful of beneficial health effects and (mercury contamination not withstanding) no negative effects. So whichever dimension of overall health is most important to you, you should eat whole grains, vegetables, fruit, nuts and seeds, and probably fish as well.