Srisatta playing a video game in his room while undergoing a study on the health effects of ultraprocessed foods at the National Institutes of Health in Bethesda, Maryland. — AP
SAM Srisatta, a 20-year-old Florida college student, spent a month inside a government hospital in Bethesda, Maryland, playing video games while scientists documented every morsel he ate.
From big bowls of salad to plates of meatballs and spaghetti sauce, Srisatta took part in a nutrition study exploring the health effects of ultraprocessed foods, which make up over 70% of the US food supply.
“Today my lunch was chicken nuggets, some chips, some ketchup,” said Srisatta, one of 36 participants paid US$5,000 to devote 28 days to science. “It was pretty fulfilling.”
The study, led by National Institutes of Health (NIH) researcher Kevin Hall, examines whether ultraprocessed foods cause people to consume more calories and gain weight, potentially contributing to obesity and other health issues.
Srisatta eating a lunch of chicken nuggets and chips in his room at the National Institutes of Health. — AP
US Health Secretary Robert F. Kennedy Jr has made nutrition and chronic disease a key priority, blaming processed foods for various illnesses affecting Americans, especially children.
He has vowed to remove them from school lunches, saying they are “making them sick”.
Ultraprocessed foods – typically high in fat, sodium and sugar – are cheap, mass-produced, and contain additives not found in home kitchens. Think sugary cereals, crisps, frozen pizzas, fizzy drinks, and ice cream.
Their rise coincides with increasing obesity and diet-related diseases in the United States and beyond.
Clinical research nurse Monica Falcon preparing to draw blood from Srisatta at the National Institutes of Health. — AP
Past studies have linked ultraprocessed foods to negative health effects, but whether it’s the processing itself – or something else – remains uncertain.
A 2019 study by Hall suggested these foods led participants to eat around 500 calories more per day than when consuming unprocessed foods.
Hall’s new study seeks to expand on this by testing whether certain ingredients – such as irresistible combinations of fat, sugar and sodium – make people overeat.
Another theory is that these foods are more calorie-dense per bite, making it easier to consume excess calories without realising.
During his month at NIH, Srisatta wore monitors on his wrist, ankle and waist to track movement and provided up to 14 vials of blood regularly.
A metabolic chamber outfitted with sensors to measure how a subject uses food, air and water at the National Institutes of Health. — AP
Once a week, he spent 24 hours in a metabolic chamber – a tiny, sensor-equipped room measuring how his body used food, water and air.
His meals, delivered three times a day, were carefully designed by NIH dietitian Sara Turner.
“The challenge is getting all the nutrients to work while keeping the meals appetising,” she said.
Srisatta was free to eat as much or as little as he wanted, but all food was meticulously weighed and measured. He was allowed outside but only under supervision – to prevent snacking.
“It doesn’t really feel that bad,” he said.
Cook Jeff Tait, nutrition research manager Merel Kozlosky and research dietitian Sharonne Waters preparing a meal for Srisatta in a kitchen at the National Institutes of Health. — AP
At a scientific conference in November, Hall reported that the first 18 participants on an ultraprocessed diet – specifically engineered to be hyperpalatable and energy-dense – consumed about 1,000 more calories per day than those eating minimally processed foods, leading to weight gain.
However, when these foods were adjusted to be less calorie-dense, consumption decreased, even though they were still ultraprocessed.
Not everyone agrees with Hall’s findings.
Dr David Ludwig, an endocrinologist at Boston Children’s Hospital, criticised Hall’s 2019 study as “fundamentally flawed by its short duration”.
Scientists have long known that people can be made to eat more or less for short periods, but those effects may not last, Ludwig argued.
Hall examining whether ultraprocessed foods cause people to consume more calories and gain weight, potentially contributing to obesity and other health issues. — AP
“If they were persistent, we would have the answer to obesity,” he said.
Ludwig called for larger, longer studies – lasting at least two months – with “washout” periods to distinguish diet effects.
Otherwise, Ludwig warned, “we mislead the science”.
Marion Nestle, a nutrition and food policy expert, acknowledged concerns about study length but said funding remains a barrier.
“To resolve that, Hall needs funding for longer studies with more participants,” she said.
The NIH spends about US$2bil annually – 5% of its total budget – on nutrition research.
A salad prepared for Srisatta. — AP
However, recent cost-cutting measures have reduced the capacity of the NIH’s metabolic unit, limiting the number of participants Hall can study at any time.
Currently, only two participants are enrolled, with two more planned next month – meaning studies take months longer than necessary.
Srisatta, who hopes to become an emergency room doctor, said the study has made him more curious about how processed foods affect health.
“I think everyone knows it’s better to not eat processed foods, right?” he said.
“But having the evidence to back that up in ways the public can easily digest is important.”
Meanwhile, the future of NIH nutrition research remains uncertain.
Each item of food is meticulously labelled. — AP
The agency, like many others, is feeling the effects of budget cuts imposed by President Donald Trump and his billionaire aide Elon Musk.
Jerold Mande, a former federal food policy advisor, supports Kennedy’s efforts to tackle diet-related diseases.
He has proposed a 50-bed research facility where nutrition scientists can study the long-term effects of specific diets on volunteers like Srisatta.
“If you’re going to make America healthy again and address chronic disease, we need better science to do it,” Mande said. — AP
