Is It Healthy to Eat Just Once a Day?
Published: 01:11 PM,Nov 11,2024 | EDITED : 05:11 PM,Nov 11,2024
“One meal a day is not a good idea,” said Dr. Caroline Apovian, an obesity specialist at Brigham and Women’s Hospital.
Apovian is a proponent of intermittent fasting in general, and she recommends it to many of her patients with obesity. Compared with eating plans or diets that require counting calories or cutting out many foods, intermittent fasting is a relatively simple way to control what you eat.
But for most people, the OMAD diet would be a disaster, she said. “If I tell my patients to eat one meal a day, they’re going to be starving all day,” she added. Then, they’re likely to overeat at dinner because they’ll rely on whatever happens to be in the house, she said.
It can also be challenging to get all of your daily calories in a single sitting, especially if you’re active. Mark P. Mattson, an adjunct professor of neuroscience at Johns Hopkins University School of Medicine, said that people who say they follow the OMAD diet probably aren’t following it exactly: They’re most likely eating more than once a day and perhaps doing so within four hours rather than one.
Apovian’s advice is to try to eat only during the hours between sunrise and sunset (which technically is a form of intermittent fasting, she said). She suggests having a protein-rich breakfast and meals with plenty of protein, fruits, vegetables and whole grains. Then, stop eating at 6 p.m. or 7 p.m., she said — which may be after sunset, depending on where you live.
Mattson himself follows an intermittent fasting routine, eating exclusively between 12 p.m. and 6 p.m. every day. In his view, the typical American diet — three meals a day, plus snacks, starting from shortly after waking to not long before bedtime — is discordant with how humans and other animals evolved to eat back when food wasn’t readily available, he said.
“Our genes and cellular systems are adapted to function very well in a food-deprived state,” he added.
What does the research suggest?
Studies on intermittent fasting tend to have a lot of limitations. They’re typically performed on small groups of people over short periods of time, and their results are often mixed. “The science is all over the place,” said Alice H. Lichtenstein, a senior scientist and professor at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University.
Some limited research suggests that intermittent fasting might help people lose weight. In one study on the OMAD diet, researchers found that when 11 physically active and healthy-weight adults had only one meal per day, in the evening, for 11 days, they lost a little more weight and burned a little more fat than when they consumed the same number of calories over three meals per day.
Other research shows that when participants restrict their eating to certain hours of the day, they end up eating fewer calories overall. That reduction in calories — not the meal timing itself — may be responsible for the weight loss.
Mattson’s own research on intermittent fasting suggests that switching between eating and fasting might turn on cellular processes that could improve blood sugar regulation, reduce inflammation and make cells better able to deal with various forms of stress.
Still, Lichtenstein said, the science isn’t clear, and we know that there isn’t a one-size-fits-all approach to how people eat.
“Everyone has a different schedule,” she said; if someone finds success with eating only between 7 a.m. and 5 p.m., that’s great. But for many people, Lichtenstein continued, “that would not work very well.” —NYT
Apovian is a proponent of intermittent fasting in general, and she recommends it to many of her patients with obesity. Compared with eating plans or diets that require counting calories or cutting out many foods, intermittent fasting is a relatively simple way to control what you eat.
But for most people, the OMAD diet would be a disaster, she said. “If I tell my patients to eat one meal a day, they’re going to be starving all day,” she added. Then, they’re likely to overeat at dinner because they’ll rely on whatever happens to be in the house, she said.
It can also be challenging to get all of your daily calories in a single sitting, especially if you’re active. Mark P. Mattson, an adjunct professor of neuroscience at Johns Hopkins University School of Medicine, said that people who say they follow the OMAD diet probably aren’t following it exactly: They’re most likely eating more than once a day and perhaps doing so within four hours rather than one.
Apovian’s advice is to try to eat only during the hours between sunrise and sunset (which technically is a form of intermittent fasting, she said). She suggests having a protein-rich breakfast and meals with plenty of protein, fruits, vegetables and whole grains. Then, stop eating at 6 p.m. or 7 p.m., she said — which may be after sunset, depending on where you live.
Mattson himself follows an intermittent fasting routine, eating exclusively between 12 p.m. and 6 p.m. every day. In his view, the typical American diet — three meals a day, plus snacks, starting from shortly after waking to not long before bedtime — is discordant with how humans and other animals evolved to eat back when food wasn’t readily available, he said.
“Our genes and cellular systems are adapted to function very well in a food-deprived state,” he added.
What does the research suggest?
Studies on intermittent fasting tend to have a lot of limitations. They’re typically performed on small groups of people over short periods of time, and their results are often mixed. “The science is all over the place,” said Alice H. Lichtenstein, a senior scientist and professor at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University.
Some limited research suggests that intermittent fasting might help people lose weight. In one study on the OMAD diet, researchers found that when 11 physically active and healthy-weight adults had only one meal per day, in the evening, for 11 days, they lost a little more weight and burned a little more fat than when they consumed the same number of calories over three meals per day.
Other research shows that when participants restrict their eating to certain hours of the day, they end up eating fewer calories overall. That reduction in calories — not the meal timing itself — may be responsible for the weight loss.
Mattson’s own research on intermittent fasting suggests that switching between eating and fasting might turn on cellular processes that could improve blood sugar regulation, reduce inflammation and make cells better able to deal with various forms of stress.
Still, Lichtenstein said, the science isn’t clear, and we know that there isn’t a one-size-fits-all approach to how people eat.
“Everyone has a different schedule,” she said; if someone finds success with eating only between 7 a.m. and 5 p.m., that’s great. But for many people, Lichtenstein continued, “that would not work very well.” —NYT