NEW DELHI: People can lose more weight by avoiding ultra processed foods, even those that make “healthy” claims, a new study has said.
The study, published in the journal Nature Medicine, which is the largest and longest clinical trial yet to examine the effects of ultra processed foods on weight, said that avoiding ultra-processed foods or UPFs; even those labelled as healthy, can double weight loss and body fat reduction compared to diets that include UPFs. UPFs are mostly high on sugar, fat and salt (HFSS).
The study found that even “healthier” UPFs with whole grains or plant-based milk were less effective for weight and fat loss.
According to Dr Arun Gupta, convenor of Nutrition Advocacy in Public Interest (NAPi), a national think tank on nutrition consisting of independent medical experts, paediatricians, and nutritionists, this rigorous randomized crossover trial conducted in the UK adds powerful scientific backing to the ongoing Indian campaign demanding mandatory front-of-pack warning labels on UPFs high in salt, sugar, or fat and ban on advertisements of UPF/HFSS food products.
The study compared ultra processed vs. minimally processed diets. Participants consumed both diets for two months each (with a washout period) and all meals were provided and nutritionally comparable in sugar, salt, fat - only the level of processing differed.
It found that even nutritionally compliant with the UK's Eatwell Guide UPFs such as wholegrain cereals, protein bars, and flavored yogurts led to slower weight loss and poorer appetite control compared to minimally processed foods.
“The study demonstrates that UPFs are not only nutritionally poor but biologically and behaviourally addictive and harmful. It validates the need for clear warning labels and restrictions on marketing, especially exposure to children. It suggests that reformulation alone is insufficient; level of processing must be a regulatory factor,” Dr Gupta added.
Urging the Food Safety and Standards Authority of India (FSSAI) and Ministry of Information and Broadcasting (I&B) to act decisively, public health experts, argue that regulatory delays and the government's overreliance on vague terms like “misleading” in advertising law are undermining the fight against obesity and non-communicable diseases.
“This study puts beyond doubt what many of us have long said: it’s not just about ingredients; it’s about the way food is processed. Since most of the UPFs are high on fats/sugars and salt, FSSAI must now adopt strong, clearly worded front-of-pack warning labels while amending its regulations” said Dr. Gupta, who is a paediatrician and nutrition advocate, said.
NAPI called for treating UPFs as a distinct and unsafe category of food, requiring stringent regulation to end advertisements and marketing of the HFSS food products as recommended by the Economic Survey 2024-25.
As India moves toward its 2025 target of halting the rise of obesity and diabetes, this study offers a wake-up call to policymakers to focus on processing levels as much as nutritional thresholds and take swift action to protect the health of the public, especially children, Dr Gupta said.
India also shows a rapid growth of UPFs at CGAR of 13.37%, from 900 million USD to 37.9 Billion USD. It means per capita UPF sales increased from Rs. 37 to Rs. 1964, a 53-fold rise.
“It is during this period that obesity almost doubled. To halt obesity, action has to reduce this consumption speed,” he said.
Given the new trade agreements signed with the UK, UPFs /HFSS food will be imported cheaper.
“That may further increase consumption and put a risk to peoples’ health. While the UK is set to enforce a 9 PM watershed on HFSS products advertising on television and already uses a traffic light warning label system in front of the pack of HFSS food products; India has no comparable legal safeguard on labelling as yet. India's weak laws to control advertisements are open to interpretation, allowing full freedom to the food industry,” he added.