They have been reviled as ' fattening'. In fact, they are an excellent primary food for the human animal. Excess calories are stored as fat. We have evolved to be able to do that. It is a store against hard times, it is the nutritional bank account that allows ovulation, growth of a foetus, and milk production.
Weights remain stable, or even reduce slightly.
Presumably this is because nuts are 'slow burners', and therefore keep you from feeling constantly hungry for calory laden sugar. A similar result was found when pecans were added to the standard diet. Other studies have shown those people who include nuts in the diet are at significantly lower risk from coronary disease. It takes about an hour for the lipids to peak in the bloodstream, and then they dropped away more rapidly as well. The fat from whole nuts is delivered in a different way in comparison with the pressed oil.