After thirty, the metabolism slows down, the body retains water and from this excess volumes and cellulite. And all the fault is low physical activity! Remember yourself as a child !? We ate everything we wanted and sweets, chips, fries, etc., drank Coca-Cola, lemonades and nothing was put off, because they were running around like crazy all day long, and now children mostly sit at home with gadgets, there is no physical activity, therefore there are also many children diagnosed with obesity. So if you want to be thin and fit until old age, eat less garbage and move more, and also ... and drink clean water!
An interesting question. Could it be social attitudes? The figure mentioned here is 30 years. Count. This is the time of such fat guys with gold chains, with purses full of dollars - "masters of life". I am not claiming. But I saw how the stereotype changed. At school, we had a guy in our class - the subject of ridicule. 175 in height, not stupid, we ourselves MADE him stupid ... I often remembered him in the 90s. He would be the standard of the "master of life". It was in those days that this cliché of a "successful person" appeared in life, and always with a tummy, as a sign that he had never "plowed". He was born so successful, with money. In a crimson jacket, cropped short (or bald head, did you notice that this is now also a SYMBOL?). It seems that the days when "pitching", "athletes" were just "meat" and cattle for slaughter are returning. Now, too, do not hesitate to "belly" and bald spots. But the attitudes that you accept as a worldview affect everything, from earrings, or there pigtails, to the perception of others. And is this building our world? Or it will pass, just a couple of beaten faces ...
And I would still talk about 30 as a milestone. On my own, I noticed from many of my friends - yes, many who were slender deer began to gain weight, about 30 years, plus or minus. And the reason is the slowing down of metabolism , age is such a thing.
But it can be overclocked. When I saw that I was over 70 kg, I took up training, but they did not help, only the muscles tightened, and the weight stood. Then I undertook to limit what I ate and it turned out that my problem was really overeating, I threw off 18 kg in six months, in detail about my experience in the blog - https://olyapka.ru/2018/01/ehffektivnyjj-sposob-pokhudet-podschet-kalorijj-mojj -opyt /.
Now I also continue to monitor the amount of food eaten, keep weight, exercise regularly (they just help to keep in good shape and be more active and invigorated). But metabolism is such a thing, once I ate everything and chocolate, eating cakes and ice cream, and still was slender as a doe. Now that doesn't work).
People get fat regardless of age, now even children have a high percentage of obesity, which has never been observed before. When doctors diagnose fatty liver disease in children (fatty hepatosis), it means that all civilized humanity is in a terrible state.
This is due to decreased physical activity
High carbohydrate food
Increasing food volume
With age, all this accumulates and is intensified by the aging of the body. For example, less testosterone is produced, men become more passive, less likely to expose themselves to physical exertion. Calorie consumption rises, fat begins to accumulate.
But you shouldn't talk about 30 years as some kind of milestone. The problem is relevant for absolutely all ages. Today teens are less active than old people in the 60s, and calories from food have doubled.