Intermittent Fasting for Weight Loss: What the Science Says
Intermittent fasting for weight loss is an effective way to reduce unwanted fat, especially for those who are obese or have metabolic syndrome. Multiple studies have found that the metabolic effects of intermittent fasting, combined with the calorie deficit that intermittent fasting tends to produce, help create a downward trend on the scale.
There are many different styles of intermittent fasting, so it’s important to find an eating pattern that works for you if you’re about to embark on this approach. , 16:8 Intermittent fasting, whether it’s a gentler approach like intermittent fasting, should be sustainable and fit your lifestyle.
In this article, we analyze the science behind intermittent fasting for weight loss and which approach works best. We’ve talked about the best ways to lose weight sustainably and safely. increase.
How does intermittent fasting help with weight loss?
Intermittent fasting can be effective in losing weight in people of all sizes, according to a report in Nutrition Reviews (opens in new tab)Most research has focused on trials of alternate-day or all-day fasting, but there is also evidence supporting the success of timed diets. It may provide cardiometabolic benefits in obese individuals, as seen in another review of the Annual Review. (opens in new tab).
Similar to how the keto diet can help you lose weight, intermittent fasting can put you in a state called ketosis, where you’re using ketones as fuel. The body metabolizes fat to produce ketones, which the body can use as an alternative energy source.
“After eating, the body goes through four different metabolic states as it digests the food,” explains Dr Deborah Lee, MD of Dr Fox Online Pharmacy. (opens in new tab)“These are the fed state, post-absorption state/early fasting state, late fasting state, and starvation.
Having worked for many years in the UK’s National Health Service, first as a General Practitioner and then as Chief Clinician for the Integrated Community Sexual Health Service, Dr Deborah Lee is now focusing on women’s health and promoting health and medical care. I work as a writer. She is a menopausal specialist.
“Most of the time, the body uses glucose for energy. After eating, blood sugar levels rise and fat is stored as triglycerides in adipose tissue. Under normal conditions, the body uses glycogen stored in the liver for energy. However, after 12 hours of fasting, all glycogen in the liver has been depleted.The body is now forced to take triglycerides from adipose tissue and break these down into fatty acids and glycerol. Fatty acids are converted into ketone bodies and used as fuel instead of glucose.”
She adds that when the body transitions from a post-absorptive state to a fasting state, she calls this a “metabolic switch.”
“At this point when the switch is turned on, the body starts using ketones for energy,” she says. “In the fed and postabsorptive states, the major hormone is insulin, whereas in the fasting state, the major hormone is glucagon.”
Intermittent fasting also works by limiting your overall caloric intake and making you calorie deficient (burning more calories than you expend). Even if you eat more after fasting, you probably won’t eat as much as you would with your normal eating pattern. A calorie deficit is one of the most effective ways to lose weight, according to a report in the Journal of Obesity and Metabolic Syndrome. (opens in new tab)so this aspect of intermittent fasting can also help you lose weight.
What is the best intermittent fasting plan for weight loss?
Dr. Sam Watts, Founder of Mind Body Medical (opens in new tab), tells Live Science that there are two clear leaders when it comes to intermittent fasting styles. “Much clinical evidence exists for the potential weight loss benefits of various intermittent fasting regimens,” he says. A less extreme and easier to adopt approach is the 16:8 model, a timed eating version of intermittent fasting that consumes all calories in an eight-hour window. , fasting for the remaining 16 hours.
“This approach is arguably the more sustainable model and has been consistently shown to induce significant and progressive weight loss.”
fasting for 24 hours
24-hour fasting is one of the most severe styles of fasting, where you either fast completely or severely limit your calorie intake for 24 hours (often one or two days a week). This may not be the best fasting method for many people as it does not fit many lifestyles. Also, long-term fasting (48-72 hours) can trigger a starvation response and encourage the body to store fat. when you eat
5:2 Fasting
This style of fasting is a flexible fasting style where you fast two days a week and eat normally the rest of the time. On fast days, limit your calorie intake to 500-600 calories. Usually this he consumes in one meal at the beginning of the day and fasts until the next morning.
fasting every other day
Alternate day fasting involves eating until you are full on alternate days and fasting every other day. While some people fast completely, they typically burn up to 800 calories a day on their fasting days.
“Using this approach, you’re fasting on alternate days, separating the non-fasting days into a healthy, balanced diet,” says Watts. has been shown to promote significant weight loss.”
Time limit: 20:4, 16:8, 14:10, 12:12
A timed diet is a style of fasting where you fast for a period of time and eat for the rest of the time slot. Common types of timed fasting include 20:4, 16:8, 14:10, or 12:12, where the first number is the fasting window and the second number is the eating window. There is no evidence that one is better than the other.
How to be successful with an intermittent fasting plan
keep hydrated
Annals of Nutrition and Metabolism research (opens in new tab) journal We’ve found that proper hydration can help keep energy levels consistent and stabilize moods, indirectly keeping cravings at bay and stabilizing motivation levels.
Watts suggests drinking plenty of water and non-calorie beverages to keep hunger at bay. “When hunger symptoms appear during a fasting period, drinking water, herbal teas, or other calorie-free beverages can help fill you up, make you feel less hungry, and generally make your life more comfortable.”
Investing in the best water bottle can also help you stay hydrated.
Choose a fasting style that suits you
A study from the Obesity Society found that alternate-day fasting in healthy-weight women can impair glucose response, so this may not be the optimal style of fasting for women. Mor agrees that women may need to be more careful with intermittent fasting than men. There has been some evidence that men can benefit from intermittent fasting, but women can be adversely affected.
“Intermittent fasting may be easier to fit into a typical workday, when you’re busy during the day and need to eat,” says Dr. Lee. He plans his meals and prepares them in advance. You can also more easily practice intermittent fasting in your social life. Accept invitations only on non-fasting days. ”
But intermittent fasting can come with side effects, she says.
“Studies of people who fasted during Ramadan show that severe hypoglycemia can occur during fasting. may not be suitable for the elderly.”
Our feature on intermittent fasting for beginners: Expert tips to get you started has more information for intermittent fasting beginners.
eat food that fills you up
Dietary fiber acts as a bulk that takes longer to pass through the digestive system, so eating foods high in fiber can help keep hunger at bay.A study published in the Journal of Nutrition (opens in new tab) We concluded that dietary fiber intake promotes weight loss and dietary adherence in adults on a calorie-restricted diet.
Additionally, protein has been shown to help with satiety, as shown in a review in the British Journal of Nutrition. (opens in new tab)Feeling satisfied after eating can help you stick with your fast because you are less likely to experience hunger and cravings for food.
“During the non-fasting period, it’s essential to eat enough healthy calories to allow you to grow during the fasting period,” says Watts. Eat enough to leave you feeling completely satisfied and full. It’s also important to eat enough healthy fats, such as virgin coconut oil and olive oils, omega-3 fatty acids, nuts and seeds, which help stabilize blood sugar, maintain energy, and fight extreme hunger. It helps prevent.”
This article is for informational purposes only and does not provide medical advice.
