Rachel Cheatham, a nutrition expert and the founder of Foodscape Group, took up intermittent fasting because she’d heard it could help with sleep: As a researcher in the field of how food, mood and diet relate, Cheatham had noticed she couldn’t fall asleep easily when she ate a late dinner, so she began experimenting with changing her meal times to see how it would impact her sleep. Over time, Cheatham started eating dinner earlier and earlier—and getting better sleep—until she gradually transitioned into a full-on intermittent fasting approach with a true time-restricted feeding window. “I started as a geeky scientist reading all the literature about the data on fasting, but in the end, it became more of a personal curiosity that led me to realize, ‘Wow, this really works. I’m just going to keep doing it,’” Cheatham said. She lost 25 pounds in the process without truly trying, even while eating desserts every day (she eats mostly plant-based foods but loves to bake and doesn’t deny her sweet tooth). But Cheatham says the results have gone well beyond weight loss. “I was trying to see how my energy levels felt, my thinking, my sleeping, and I let that be the guide, and the side effect was this weight loss,” she said. Today, Cheatham regularly maintains a 10 a.m. to 4 p.m. eating window (slightly narrower than the popular 16/8 diet) and her husband has hopped on board, too. He eats from 2 p.m. to 10 p.m. so they dine together for one main overlapping meal a day—her dinner, his lunch.
Intermittent fasting 16/8 results
There are a number of different takes on intermittent fasting, from the 16/8 method to a full 24-hour fast once or twice a week. to the 5:2 diet, which involves restricting your calorie intake to 500 calories per day for any two non-consecutive days while eating your normal diet the other five days of the week. One of the most popular and approachable is 16/8 intermittent fasting, in which you fast for 16 hours a day and eat within the remaining 8 hours. It’s typically considered the easiest to do because it gives you a flexible eating window during the day (such as 10 a.m. to 6 p.m.) in which you can eat whatever you want. Often those on the 16/8 plan will skip breakfast or have black coffee or water and then fit in two meals, such as lunch and dinner. “You already fast every single day as you sleep. Intermittent fasting just extends the fasting period a little further. The main aim is to lose weight without involving any specific diet imposition,” said Dr. Carrie Lam, a primary care physician with a focus on integrative medicine and nutrition. Aside from weight loss, one of the more significant benefits of intermittent fasting is not seen outwardly, but occurs at the cellular level, explains registered dietitian Trista Best. “It starts a form of waste removal called autophagy, which removes damaged cells and proteins. This process is responsible for improving overall health and preventing many chronic diseases like cancer,” she says. Research on intermittent fasting has shown it results in an impressive list of health benefits, including weight loss, lower blood pressure, and reduced insulin resistance. But as Cheatham’s own results show, many people who partake in intermittent fasting also report feeling cognitively clearer, having increased energy levels, better sleep patterns, and even reduced cravings or urges for snacking. “What is good for your body, is often good for your brain,” says nutritionist Melissa Kathryn.
Intermittent fasting results for women
Jenna Lessner, a certified holistic nutritional consultant, notes that little research has looked at the impacts of fasting on reproduction in women. Animal studies, however, have shown that fasting might interfere with fertility and reproduction cycles in females. According to Lessner, women are more sensitive to signals of starvation, and breaking a fast may result in insatiable hunger. “A woman’s body wants to protect a potential fetus, even when we are not pregnant,” Lessner explains. Some women have also experienced irregular cravings leading to binge eating, lost menstrual periods, and a decrease in energy, she says. For these reasons, it’s suggested that women take a modified approach to intermittent fasting, such as shorter fasting windows or fewer fasting days. “To make intermittent fasting work for you, you need to have a personalized approach,” said Anju Mobin, licensed nutritionist and managing editor of Best for Nutrition. “Depending on your schedule, sleeping time and social life, spread your eating and fasting phases. Intermittent fasting should not make you cranky or starving all the time. Intermittent fasting may not be the right choice for everyone. Listen to your body, and do what is right for you.” Women who are pregnant, breastfeeding or trying to conceive should not partake in intermittent fasting because their bodies require additional nutrients for their child. In addition, people with diabetes or other medical conditions such as heart disease should be aware intermittent fasting can cause abnormalities in electrolytes and blood pressure. Intermittent fasting is also not recommended for individuals with eating disorders.
How long does it take to see results from intermittent fasting?
While results will ultimately vary from person to person, Krista Varady, a nutrition professor at the University of Illinois Chicago whose research focus is intermittent fasting, says people typically see weight loss results immediately. Varady has spent more than 15 years conducting weight loss studies based on fasting (her specialty is alternate day fasting), and in her research, she’s found that most people lose 1 to 3 pounds per week, as soon as the first week. However, other long-term health benefits such as decreased blood pressure and cholesterol are typically seen in 8 to 10 weeks. Newcomers to intermittent fasting should also be mindful that it takes at least 10 days to feel adjusted to the ups and downs of this new eating pattern. When first starting out with intermittent fasting, some report feeling cranky, low-energy, or starving. “After 10 days, most people feel fine,” she says. The most important consideration for producing long-term results is to look at intermittent fasting as a lifestyle change, not a short-term fad diet. “It’s important that a person follow a diet that works for their lifestyle over the long term. If they use a certain diet—fasting or otherwise—to lose weight and then they go back to their normal eating habits, they will just gain all the weight back,” Varady says. Cheatham, who has maintained her 10 a.m. to 4 p.m. eating window over the last two years, agrees that intermittent fasting has become a lifestyle change she isn’t looking back on. She lost the weight in her first year of fasting and then saw her weight stabilize, but Cheatham continues to practice intermittent fasting because of the other benefits she’s experienced—improved sleep, mental clarity, and increased energy levels, to name a few. “Eating in a time-restricted window is singlehandedly the best thing I’ve done to improve my eating satisfaction, my sleep, my mood, my energy level and, yes, my body weight,” she says. “If and when I do eat a more traditional dinner at that bewitching dinner hour, then I feel rather crappy, overly tired but unable to sleep soundly, and just off. That’s the biggest motivation I need to resume my usual intermitting fasting routine.” Next up, here’s what to know if you’re considering combining intermittent fasting and keto.
