Researchers at Ben-Gurion University of the Negev in Beersheba found diets frequently produce a swift weight decline, mainly in the first four to six months, followed by weight stabilization or even regain despite continued dieting.
The partial regain should not discourage people from sticking to healthier dietary habits, they said.
"This study tells us that we may have all been too tunnel-viewed on weight when it comes to healthy dieting," Faculty of Health Sciences Professor Assaf Rudich said.
"Although maintaining ideal body weight is linked to better health, when it comes to adopting healthier dietary habits in mild to moderately obese people, there are benefits beyond weight loss, such as decreasing inflammatory tone and elevating 'good cholesterol' [HDL]."
In obese people, health benefits of switching to healthier dieting extend beyond the single outcome of weight loss, the researchers said.
"In fact, important improvements that likely signify decreased risk for cardiovascular disease occur even despite weight regain, as long as dieting persists," Rudich said.
The findings contain a strong message for the public, one researcher said.
"Switching to a healthy lifestyle is a long-term strategy that should be done moderately but persistently," principal investigator Iris Shai said.