A study involving two-thirds of the US population showed that six cancer-related crusts had grown during this period. The younger ones were obese adults, the faster the incidence of one of these types of rake, the results of which were published in the medical journal The Lancet Public Health.
For the study period, for example, the incidence of foot-and-mouth disease among adults aged 45 to 49 years increased by about 1% per year. Among those aged 30 to 34 years, it increased more than twice a year. Of those aged 25-29, the incidence of foot-and-mouth disease increased by up to 4.4% per year, according to AFP news agency AFP.
Similar to four other cancers associated with obesity, the annual increase in its incidence was higher for those in the 25-29 age group. In renal cancer, the annual increase in incidence in this age group was 6.23%, gall bladder 3.71%, uterine cancer 3.35% and colorectal cancer 2.41%.
When it comes to one of the cancers of bone marrow, multiple myeloma, its incidence increased more rapidly among young adults in the early 30s.
"Our findings reveal the recent change and may serve as a warning for the future increase in the incidence of obesity-related cancer among older adults," said co-author Ahmedin Jemal of the American Cancer Society.
As AFP points out, the number of women in the US in the last four decades has more than doubled. Obesity has also increased markedly in other rich countries and recently in developing countries. In today's world, about two billion people are obese or overweight.
Cancer, with a few exceptions, has historically been considered an age-related disease. Researchers in the new study also pointed out that the number of new cancers remained much higher among older adults, although the rate of increase in their incidence is now the highest among young adults.
For example, between 2010 and 2014, for every 100,000 people aged 24-49, two cases of foot-and-mouth disease were diagnosed, while for every 100,000 people aged 50-84, there were 37 cases of foot cancer.
The number of people in the United States who die from cancer has generally fallen. From 1980 to 2014, about 20 million people died of cancer, with mortality from that disease falling by 20 percent from 240 to 192 deaths per 100,000 people, partly due to a decline in tobacco use. "But obesity can change this trend in the future," Jemal warned.
"Obesity in the United States and the UK today is one of the most potentially cancerous causes. Twelve of the cancer cases in the United States cause overweight and more than 20 in the United Kingdom," he added.
Jemal and colleagues analyzed all cancers in 25 US states, where about 67 percent of the US population lives between 1995 and 2015. They also relied on previous research. The data they captured is related to 30 types of cancer, 12 of which have been linked to obesity in the past.
Of the 18 remaining types of cancer, only two showed a similar trend, that is, an increase in incidence among young adults. Other cancers remained at the same level or, in the case of those related to smoking or infections, fell.
When the study was published, researchers called for a more intensive screening for obesity at the primary health level, and called on doctors to warn patients about the risk of cancer in case of severe overweight. Currently, fewer than half of US physicians in the United States regularly measure their patients' body mass index.
Hyoun Sung, one of the study's authors, also referred to the American Cancer Society, noted that the quality of the American diet has deteriorated in the last decades. More than half of adults between the ages of 20 and 49 consume many fruits, vegetables or whole grains, but there are many salts, fast foods and soft drinks.