Maggie's Farm

Keto-style nutrition (ketogenic) is only for people whose habits and life-styles tend towards excess fat deposits. There is no reason to fuss with your nutritional habits if you are in good shape and good conditioning. Food is not medicine - but if you lift heavy 2-3 times weekly, keep the protein up for muscle repair.

All "keto" means is that you are burning fat. Burning fat is difficult, because your body wants to hang on to it and exercise does very little for that at ordinary intensities and durations. 

Kruiser explains it here:  Jillian Michaels Is Mad That Keto People Lose Weight Without Buying Her Products

An interesting side effect of ketosis is that appetite tends to be reduced and energy increased. For people who are serious about it, you can buy Keto-strips to check your urine. That will instantly tell you whether you are burning fat or not.

If overweight, you probably have some degree of insulin insensitivity, sometimes termed "pre-diabetic" at some point. A keto nutritional habit can correct that, but remember that if you have ever been fat, your body will want to restore it back to where you set your highest weight. Fat cells are as greedy as governments and they never forget.