My problem with the focus on weight is whether it actually distracts us from the real problem. Maybe the real problem is the 30 million Americans who have diabetes. Perhaps it is the diabetes (both T1 and T2) which is resulting in the weight gain.
Unfortunately the diet and exercise recommendations don’t pan out. The DPP showed that it just doesn’t work changing lifestyle has virtually no effect on outcomes, after 15 years the majority of patients still ended up progressing to full blown diabetes and taking metformin worked just as well as lifestyle changes (and both were only slightly better than doing nothing)