For about 97% of people body fat % and weight simply comes down to mathematics. More calories consumed than burned through metabolism/exercise = weight gain. More calories burned and fewer calories consumed = weight loss.

It’s pretty simple!

We try to make things too complicated and convenient when we try to lose weight. We want everything to taste like cookies and pizza and we want to exercise no more than 5 minutes at a time, and it has to be fun! The harsh reality is that if you are looking for shortcuts you’ll never lose weight because its hard work and dedication to the diet that really work.

Genetics plays a big part in it, I come from two overweight parents, but I know that if I want to lose weight I need to understand my body and my metabolism and make adjustments accordingly.

It seems that just means some people (in our lives of oversupply of food and sedentary lives) which do a more efficient job of turning calories into fuel and fat have to eat less than those that are inefficient at doing that if they don’t wish to gain weight. My guess is most of those wish they were less efficient but so far we haven’t figured out how to make people absorb fewer calories in a healthy way. My guess is we will at some point. On the other hand their ancestors were probably happy for that trait in an age of scare food and demanding physical needs.

Obviously there are additional complexities but this difference in our bodies efficiency just means different people have to eat different amounts to be health (which makes perfect sense).

You said, “The whole healthy eating debate is sure not easy to figure out. But I think some things are clear. Eating too many calories and not exercising enough are problems. And it also makes sense that it is not only the number of calories that matter but what type. We are biological beings and how we process food is not just by a count of the calories.”

I’m the curious sort myself. I began studying nutrition about 30 years ago after sustaining a back injury. I would have terminated my investigations after 4 or 5 years were it not for the controversies over caloric intake and saturated fat consumption.

Caloric intake may or may not be related to weight gain depending upon biochemical and physiological makeup. Benjamin Franklin is credited with the observation, “You are what you eat.” More recently, Jeff Volek noted, “You are what your body does with what you eat.”

What most scientists don’t realize is that caloric absorption efficiency varies widely. At one extreme are those with small stomachs, short intestines, and a very active gut microbe population. This sort of physiological digestive makeup is associated with reduced caloric absorption efficiency. This would explain why some people can consume enormous amounts of food without gaining weight.

For further discussion I suggest you Google “David Brown calorie excretion” or “David Brown unabsorbed calories.” I also urge you to read “Biochemical Individuality” by Roger J. Williams, PhD.