The human body uses energy and nutrients from foods to do work and to build and repair tissues. If it has extra calories, it stores them as fat. This is normal operations — humans evolved in conditions of modest food security, so it should not surprise us that we are descended from people who made the best of sometimes very bad situations. And in order to do its work, the body will use any source of calories — protein, fat, carbohydrate — for energy. If the only thing we needed food for was energy, that would be the end of the story. But we need more.
It Still Matters Where You Get Your Calories
As the famous historical example of scurvy in sailors shows us, navies throughout the world had to give thought to how to provision ships for long voyages in order to prevent both food spoilage and malnutrition. You can’t live on Twinkies alone — at least not well, and probably not for long. Even the “Twinkie Diet” guy didn’t; he had a daily protein shake, canned vegetables, and a multivitamin to ensure that he had his basic nutrients. (He also exercised every day, which certainly contributed to his health.)
Blood Sugar and Satiety
Foods do have different effects in the body. Some people have less stable regulation of blood sugar than others, and may feel worse when they eat refined carbohydrates, especially sugars. An extreme example of this is people with diabetes, who must take care in how they put together the foods they eat, and space their meals throughout the day.
Different foods also leave us more or less satisfied or full. Protein-rich foods and fats are more satiating than refined carbohydrate, for example, and fiber-rich foods are more filling. (Beware: The satiating effect of fats can be undermined by being combined with salt or refined sugar to keep you snacking on foods like chips or cookies.)
Two Budgets: Calories and Nutrients
We have two requirements for healthy eating: enough calories to cover our energy requirements, and enough nutrients to maintain our tissues and body functions. If we eat fewer calories than we need to cover our energy use, we can lose fat. However, if we are missing nutrients, we can lose muscle or worse. The one part of the “Twinkie Diet” guy’s plan you should definitely follow is to make sure you get those basic building blocks in your diet.
Image: illustration by Christina Jung, created for an edition of Animal Farm.