When’s the worst time in adulthood to pile on the pounds?
This could explain why some hefty people make it to 90 while others die much earlier from obesity related complications.
A large study from researchers at Lund University in Sweden looked at how changes in weight, from late adolescence through mid-adulthood, relate to long-term health.
The results suggest that gaining weight earlier in adulthood may carry the greatest long-term risks.
The findings were published in eClinicalMedicine.
The research analyzed data from more than 600,000 people.
Instead of looking at weight at just one point in time, the researchers tracked how body weight changed between 17 and 60.
Participants were included only if their weight had been measured at least three different times.
These measurements often came from official records — such as military conscription exams, pregnancy care visits or participation in medical studies.
Over the course of the study, 86,673 men and 29,076 women died, allowing researchers to examine how earlier weight patterns related to long-term mortality.
Faster Adult Weight Gain and Higher Mortality
On average, participants gained about 0.88 pounds or 0.4 kilograms per year.
But those whose weight increased more quickly tended to face greater health risks later in life.
The timing of obesity also made a difference. Individuals who developed obesity between 17 and 29 had about a 70 percent higher risk of premature death compared with people who became obese only after age 60.
We can know, from an intuitive or logical standpoint, that the longer someone’s body is fat, the more harm this will cause over time.
Why Early Obesity May Be More Harmful
Longer exposure to the metabolic strain of being signficantly oveweight can shorten life.
Excess body fat influences inflammation, hormone levels, insulin function and cardiovascular health.
Over decades, these effects can accumulate and contribute to chronic disease.
The researchers did find one interesting exception in the results.
For cancer in women, the timing of weight gain did not appear to significantly change the level of risk.
Whether weight gain occurred earlier or later in adulthood, the association with cancer mortality looked fairly similar.
If longer exposure to obesity were the main factor driving cancer risk, earlier weight gain should have produced higher risks.
Because that pattern didn’t appear, the team believes that other biological processes may also be involved.
One possible explanation involves hormonal changes.
During menopause, shifts in hormone levels can influence body weight, fat distribution and metabolic processes.
These changes might affect cancer risk independently of when weight gain occurs.
A Study Strength
Many earlier studies rely on people trying to remember how much they weighed years or decades ago. Those recollections are often inaccurate.
In this study, most weight measurements were taken directly by medical staff in clinical or official settings.
Because the data came from objective measurements, the findings are considered more reliable.
The Idea of an “Obesogenic Society”
Cheap high-calorie foods are widely available; many jobs plus our home lifestyle can involve prolonged sitting, and daily life often includes less physical activity than in the past.
Because of these conditions, some researchers describe today’s environment as an “obesogenic society” — one that promotes weight gain.
Obesity has been associated with a wide range of health conditions. The fact that thin people as well can acquire these same conditions is not the least bit relevant and doesn’t excuse obesity as a prime driver of chronic illness.
• Cardiovascular disease, including heart attack and stroke
• Type 2 diabetes
• Hypertension (high blood pressure)
• Non‑alcoholic fatty liver disease
• Certain cancers including that of the colon, liver, kidney and breast (postmenopausal)
If you’re a young adult who’s gotten pretty heavy lately, it would be a big mistake to think, “I’m still young; my body can handle it.”
Something the study didn’t cover is the fact that the longer that a body is fat, the more time that this fat will cause substantial strain on the knee joints.
So if you’re young now but very overweight and “feel fine,” you should think about what your knees will be subjected to over the next 20 years if you remain extra heavy in size. Obesity is a big risk factor for the need for a total knee replacement.
