The One Meal a Day Diet (OMAD) might have some A-list fans, including Bruce Springsteen and Chris Martin, but is this limited way of eating actually beneficial for our bodies? We spoke to a dietitian to find out more about the risks and advantages of the restrictive approach to food. But first, what actually is it? And can you do the OMAD diet if you’re vegan?
What is the vegan OMAD diet?
According to Coldplay frontman Martin, he started to follow the OMAD diet after having lunch with hitmaker Springsteen. Speaking on an episode of the podcast Conan O’Brien Needs a Friend earlier this year, he told the host, “I actually don’t have dinner anymore. I stop eating at 4pm, and I learned that from having lunch with Bruce Springsteen.”
“I was lucky enough to go over there to lunch the day after we played Philadelphia last year,” he added. “I was on a really strict diet anyway. But I was like, ‘Bruce looks even more in shape than me.’” The secret, according to Martin, was eating just once a day. “I was like, ‘Well, there we go. That’s my next challenge,’” he continued.
Intermittent fasting is generally popular with celebrities and refers to going extended periods of time without eating. However, approaches vary significantly. Some people choose to simply skip breakfast (prolonging the natural fast we all do when we sleep overnight), while others take it to the more extreme end of the spectrum—like with the OMAD diet.
“The OMAD diet, or ‘One Meal A Day’ diet, is a type of intermittent fasting where you eat all your daily calories in a single meal, typically within a one-hour window,” explains Ana Reisdorf, MS, RD for The Food Trends to VegNews.
It is possible to follow OMAD while vegan, as there is no restriction on the type of foods you can eat, only when you can eat them.
What does fasting do to the body?
Fasting is not new. It’s a common practice in many religions, for example, Hinduism, Jainism, and Christianity, and is often thought to demonstrate spiritual discipline. Over the centuries, fasting (or hunger strike) has also been used as a form of political protest (think of Mahatma Gandhi, for example, or imprisoned suffragettes).
But now, as Martin says, this restrictive approach to diet is becoming a popular weight loss tool. “During fasting, insulin levels drop, and the body starts using stored energy, such as glycogen and fat, for fuel,” Reisdorf explains. “This can lead to weight loss.”
Reisdorf adds that fasting may also possibly induce autophagy, which is when the body’s cells essentially clean out any unnecessary or damaged parts. There is some research to back this up, but it’s worth noting that, right now, it’s in the very early stages, and most studies have not been carried out on humans.
According to Medical News Today, there is also research to suggest that exercise and a naturally occurring chemical called curcumin (found in turmeric) may also induce autophagy.
Is the vegan OMAD diet safe?
While there may be some benefits to fasting, Reisdorf does not recommend that people follow the OMAD diet for long periods of time. “Extended fasting can have potential risks and side effects, including nutrient deficiencies and muscle loss,” she explains.
Other potential side effects of fasting include low blood sugar, which can result in symptoms like dizziness, shakiness, headaches, and an increased heart rate.
Healthline also notes that extreme restriction may result in irritability, low energy, and constipation. It may also increase levels of bad cholesterol and lead to high blood pressure for some people.
OMAD diets can also consist of processed foods, like French fries and chips, as there are no restrictions on ingredients, which, as Residorf noted, could lead to an increased risk of nutrient deficiencies.
If you want to experiment with intermittent fasting or the OMAD diet, it’s important to speak with your healthcare provider or a dietitian beforehand to make sure this way of eating is safe for you. But Reisdorf is clear, this is not something anybody should be doing long term.
“I would not recommend anyone follow this diet for any extended period of time,” she says. “If you want to fast like this one to two days a week for weight loss in the short-term and you are generally healthy, I think it’s probably fine. But this is not a sustainable or healthy way to eat.”