Change in women’s hormones after menopause reduces caloric needs and their weight will increase if all other inputs will stay the same. The beauty of complex, fibrous carbs found in vegetables is the ease in maintaining normal blood glycogen levels. This causes appetite to be self adjusting. As a bonus, vegetables have low calories requiring an tremendous amount of sustained effort to gain weight. Further, a vegan’s energy levels are consistent, without the post meal energy drops that may be seen with other foods, even including meats. So instead of taking a nap after a meal, the vegan will be more likely be doing stuff and using more calories all the while.
Some of my mom’s friends are vegan, hit menopause, and absolutely have no issues with extra weight.
Now before you stumple upon an article that talks about cows, remember cows are also fed grains and hormones for weight gain.
The Meat and Dairy Association is a powerful lobby and spends an extensive amount of money on advertising. “Pork, the other white meat”. “Steak, its what’s for dinner”. I suspect this Association is behind much of the fake science concerning diets, similar to the practices of the pharmaceutical, tobacco, and industrial companies. The Meat and Dairy Association has apparently been able to influence dietary recommodations in the US. For example, compare Canadian dietary recommodations to the US, even though beef is a major Canadian export.
Further, I’m aware of a doctor who is critical of adults using dairy products over long term health concerns.
The key is to understand human energy, hormonal systems, and physiology. As a truck driver by trade, I claim no such expertise, but I have read various research studies on the subject. If you really want to take a stab at understanding the science behind various diets, read the studies and their methodologies.