When you put on weight early in adult life, it can hurt your health many years later. A huge study from Lund University in Sweden looked at more than 600,000 people. It checked how weight changes from age 17 to 60 affected the risk of dying from different illnesses.
Obesity is already known to cause many diseases. Instead of only measuring weight at one point, the researchers followed weight changes over many years. They found that gaining weight faster when you are young leads to a higher chance of early death.
"People who put on weight early are more likely to die younger than those who stay steadier," said Tanja Stocks, an epidemiology professor at Lund. The results were published in eClinicalMedicine.
The team used health records that measured weight at least three times for each person – during early pregnancy, military service, or research visits. During the follow‑up, 86,673 men and 29,076 women died.
Fast Weight Gain Raises Mortality
On average, participants added about 0.4 kg (0.9 lb) each year. Those who gained weight quickly had a higher risk of dying from diseases linked to obesity.
People who became obese (BMI ≥ 30) between ages 17 and 29 faced roughly a 70 % higher risk of early death compared with those who stayed below the obesity threshold until age 60.
Women’s Cancer Risk Was an Exception
The timing of weight gain did not change cancer risk for women. Researchers think hormones that change during menopause might explain this difference.
Why the Data Are Trustworthy
Most weight measurements were taken by health staff, not recalled from memory. This makes the results more reliable than older studies that depended on self‑reporting.
What a 70 % Increase Means
Imagine 10 out of 1,000 people die in a group. In a group with early obesity, about 17 out of 1,000 would die. Exact numbers can vary, but the pattern is clear: early weight gain is risky.
Living in an “Obesogenic” Society
Today’s world makes it easy to gain weight and hard to stay healthy. Policymakers need to create rules that help people keep a healthy weight.
Diseases Tied to Obesity
- Heart disease and stroke
- Type 2 diabetes
- High blood pressure
- Non‑alcoholic fatty liver disease
- Several cancers (colon, liver, kidney, uterus, post‑menopausal breast)
Study at a Glance
- Weight measured at least three times between ages 17‑60
- Average follow‑up: 23 years for men, 12 years for women
- Total participants: ~620,000
Key Takeaways
- The more weight you gain, the higher the risk of early death.
- Getting obese between 17‑29 raises overall death risk by about 70 %.
- Gaining 0.4 kg per year from 17‑30 (about 6.5 kg total) adds roughly a 17 % higher risk of early death.
- These patterns hold for heart disease, obesity‑related cancers, and other obesity‑linked causes.
- Women’s cancer risk did not change with the age of weight gain.