The gigantic food industry in North America and its lobbyists are happy with the concept that most people are fat just because they eat too many calories. This message relieves them of their responsibility for harm from the typical western diet that consists largely of low-cost, highly-refined "junk" foods that are full of added sugars and have most of the fiber removed. The food and beverage industries have supported the concept of excess calories causing disease in an apparent effort to downplay the harms of specific foods that they try to sell to you. When you go into a supermarket or restaurant, probably 80 percent or more of the available choices are foods that you should not eat on a regular basis.
A team of 22 respected nutrition researchers reviewed hundreds of studies, looking for dietary patterns or components of foods that might explain our epidemic of obesity and the "cardiometabolic" diseases (type 2 diabetes, heart disease, strokes and so forth) beyond just taking in more calories than you burn (Obesity Reviews, May 14, 2018). They analyzed studies of:
• specific components of foods, such as saturated vs polyunsaturated fats or the various types of sugars
• high-carbohydrate diets vs high-fat or high-protein diets
• the effects of artificial sweeteners
• foods or diets that alter the microbiome (good and bad gut bacteria)
• foods or diets that affect responses in regions of the brain
• effects of various foods during critical periods of development (gestation, infancy, early childhood)
While they stressed the need for additional research in all of these areas, in general they found that, "The food environment needs to be improved. Food policies that will improve the availability and reduce the costs of healthy foods compared with high-calorie, [overly] palatable foods are needed."
How the Food Industry Could Change
Unfortunately, the food industry is motivated only by profit, so it is highly unlikely to make changes that would result in selling less of its products. The pressure must come from consumers. Today, almost 70 percent of North Americans are overweight and 40 percent are obese (JAMA, 2012; 307: 491–497), and many will die from their poor choices of the foods they eat.
Telling people that sugared drinks can cause obesity, heart attacks and premature death has far more meaning than telling them to avoid fructose or any other specific component of foods. Most people cannot look at a food and immediately calculate its content of components that, in excess, may harm them, such as glucose, fructose, sucrose, saturated fat, or polycyclic aromatic hydrocarbons (PAHs), but everyone can learn about food groups. Instead of talking about food components, the message from the scientific community should be:
• Eat more of the foods that are associated with protection from disease — vegetables, fruits, whole grains that have not been ground into flour, beans, nuts and other seeds; and
• Eat less of the foods that have been associated with increased risk for diseases and excess weight, such as sugar-added drinks including fruit juices, foods with added sugar and refined grains, red meat, processed meats, deep-fried foods and foods that have been grilled, broiled or charred.
Individuals who are interested in their own health cannot wait for the food industry to change. Each of us faces a lifelong battle to resist the rampant promotion of foods that we do not need and to make daily healthful food choices. I recommend that you:
• Eat lots of the foods that are high in fiber, which is not absorbed in your upper intestinal tract. Fiber is found in all unrefined foods that come from plants. Insoluble fiber passes through your body without being absorbed or contributing calories and soluble fiber is broken down by bacteria in your colon to form short-chain fatty acids (SFAs) that help to lower cholesterol, blood pressure and body fat.
• Severely restrict sugared drinks, foods with added sugars and other refined carbohydrates because they taste so good that you are likely to eat too much. Sugar-added and highly processed foods raise blood sugar to high levels, which drives up blood insulin levels that are associated with increased hunger and eating more food. I think a major key to controlling weight is to avoid foods that cause high rises in blood sugar and insulin.
• Limit sources of animal protein. Many people do not realize that red meat and processed meats also raise blood insulin levels significantly because a major function of insulin is to drive the protein building blocks called amino acids into cells. There is still scientific controversy over possible health benefits or harms from dairy products, eggs or poultry. For example, plain yogurt with no added sugars and cheeses made by fermentation may well be healthful, even though they can be high in saturated fats (Am J Clin Nutr 2017; 105: 1033–1045), because the fermentation process breaks down and removes galactose. Galactose is the sugar found in milk that appears to cause inflammation and, when taken in excess, may increase risk for various diseases.
• If you are overweight and wish to lose weight, or if you are having trouble controlling your healthful weight, I recommend applying all of these suggestions in a program of intermittent fasting.