Diet, exercise, and weight are inextricably linked. In previous articles we presented some raw data on supplements, diet failures, fad diets, and even weight loss in general. In this piece, we’ll take a deeper dive into the science behind eating habits, recommendations, and how they affect overall weight, fitness, and health.
Because of the prevalence and importance of Fat and Sugar in our diets and weight loss plans, I’ve included only some general statistics for them, here. For detailed information, please read the independent articles we’ve dedicated to those subjects.
A lot of controversy has been stirred up about the Recommended Daily Allowances (RDA) for various nutrients. We’ll discuss those later, but for now, here are some general tips.
Before we get into nutrient specific statistics, some headlines can be made straight from the following macro-stats. All of these deaths were directly correlated to diet and nutrition, either eating too much or too little of something.
The Journal of the American Medical Association reviewed over 700,000 deaths from stroke, diabetes, and heart conditions. They found that:
These mortality figures can be compared with the following report from the Center for Disease Control and Prevention , juxtaposed against Gallup Survey responses. 
Trends Over Time
Tracking how well Americans follow dietary guidelines can give us a picture of how well we’re managing our nutrition through food.
Fats have been the boogeymen of diets and weight loss for decades, generations, even. But the fact is that fat is not necessarily correlated to weight gain or better health. Here are some of the first items from our Dietary Fats Statistics page:
Added Sugar and Corn-derived sugars are emerging as a critical threat to overall health. Here is an overview of what’s in our main Sugar Stats article:
Carbohydrates (Other than Sugar)
Many millions of people have tried a fad diet that calls for the limiting of all carbohydrates. This may have weight-loss benefits, but these diets also come with significant health risks.
Protein is the primary source of all muscle building amino-acids. Additionally, it can be burned for energy, replacing potentially dangerous sugars and fats in a healthy diet. There are health concerns, however, as many animal and vegetable protein food sources also come with fat and sodium.
Given that there is some controversy over plant-based proteins, due to bioavailability of the amino acids themselves, here are the scientifically proven best plant-based sources:
- Dried seaweed.
- Roasted soybeans.
- Roasted pumpkin seeds.
- Roasted peanuts, and;
- Cook lentils.
Plant-based proteins are also associated with environmental benefits and appetite control. 
Fiber is as undervalued a benefit to total health as sodium is an overlooked negative agent. Study after study has linked high-fiber diets with better health outcomes.
Some people call sodium the “silent killer,” because so many health advocates and individual consumers are preoccupied with fat and sugar. The following statistics can highlight the danger of ignoring the salt problem.
Most people associate sodium with their salt shaker, and that by using that less they will get a “low-sodium” diet. But researchers warn that “hidden sodium” in prepared foods can easily put us over the daily allowance. For instance, salt does not need to be listed on mayonnaise and other condiments. 
Where Else to Be Careful
The following is a sampling of common foods with surprisingly high sodium. 
Common Food Item
% of RDA
Canned tomato juice (1 cup)
Cheese sauce (1 cup)
Feta cheese (1 oz)
American Cheese (1 oz)
Tuna Salad (1 cup)
Bagel (3 ½ inch)
Biscuit (2 ½ inch)
Kellog’s Corn Flakes
Kellog’s Special K
Pasta & Meatballs (canned, 1 cup)
Wheat Flour (self-rising)
Lima Beans (canned)
Beans (refried, canned)
As we’ll see in the Supplements section, many Americans are aware of their vitamin deficiencies, but that hasn’t produced 100% remedial action. Here’s a snapshot of the stats behind some of the common vitamins.
It can seem as if the established scientific community has a bias against dietary supplements, and that may be the case for certain individuals. The reasons can range from doctors not wanting patients to become enamored of fad diets and supplement trends to simple prejudice. But even the scientists behind our federal nutrition regulation have recognized the need for some people to take supplements or vitamins.
Many people are using supplements for macronutrients, as well. For protein supplements, experts recommend:
200 or few calories per serving.
2 grams or less of any fat.
5 grams of sugar, or lower. 
Attitudes Surrounding Nutrition
We’ve already seen some of the micro-level discrepancies between what people actually consume versus what they answer to in a survey. The following statistics can give us nuanced insights into people’s attitudes, which may be causing these discrepancies. 
Many of these data are from surveys; we can contrast people’s answers about following diets and nutrition guidelines against the empirical data surrounding malnutrition and obesity. 
Looking at people’s purchasing trends also gives us an idea of how they’re trying to meet their nutrition goals. (Consumers may try to get their intake through a combination of purchases, as with fiber.)
Related: Diet Failure Statistics