Both your anti-gluten and low-carb stereotypes are probably doing well for their health by cutting out the simple carbs of breadstuffs and other similar foods that wreak havoc on blood sugar.
Yes, non-starchy vegetables are very good for you—and few anti-gluten or low-carb types avoid them. Some fruits can deliver sugar shocks if eaten in quantity, and I’m not so sure that fried olive oil is even as good for you as butter, lard, or other animal fats.
You are free to believe what ever you prefer. The primary issue with lard, butter, and other animal fats is that consumed out of proportion in an otherwise healthy diet they still are associated with cardiovascular disease.
Our friends who have cut gluten out of their diet are ALL having health issues, every one of them. A strange coincidence??? Maybe. Or more likely the foods they are cutting out of their diet have nutrients that are important to their good health.
As far as the “low-card” high protein diets... we know people who have pushed themselves into diabetes, organ failure, cardiovascular disease, and actually have died from their unhealthy choices. Even while their health was failing they continued to spout out diet propaganda from people and companies hoping to profit from their misinformation.
The way the diet charlatans operate is by mixing in a little bit of truth with false logic to come to an erroneous but reasonable sounding conclusion. Most people who are pudgy but basically young and healthy can go off on a diet tangent and stick with it for a few months without causing much harm. The problems arise when older people who are not so healthy to begin with try the same thing. Some of them end up with serious problems.
I believe in moderation in all things which includes a balanced diet and exercise. This is a common sense universal truth which deep down we all know is true. There simply are very few short cuts in life. Cutting out gluten and “carbs” is just silly for most people. Trying to live on mostly meat, protein powder and frozen dinners is also a bad idea in most cases. Yet my wife and I know many people who are doing these things with predictable results that are detrimental to their health.