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Intermittent fasting has generated much excitement over its potential  as a simple method to lose weight and improve health. It involves eating normally  during limited hours each day (e.g. 8 hours), and then abstaining from food the other hours (e.g. 16 hours). However, a recent study found that people following intermittent fasting for 12 weeks did not really lose weight or improve key metabolic markers. Bummer.

University of California researchers randomly assigned 116 adults, who were overweight or obese, to either an intermittent fasting group (16 hours fasting/8 hours allowed to eat ) or a group that ate 3 regular meals at set times each day (breakfast, lunch, dinner). The intermittent fasting group lost 2 pounds over the 12 weeks, which is not significantly different from the group that ate their meals at structured times - they lost 1 1/2 pounds. Same with metabolic markers (e.g.insulin levels, fasting glucose levels, cholesterol levels) - no real differences between the groups after 12 weeks.

Of course this was just 1 study, so we'll see what other human studies find. In contrast, other small human studies, as well as mice studies, have found health benefits from intermittent fasting, also called time restricted eating.

From Medical Xpress: Intermittent fasting is popular—but it doesn't work for weight loss

The currently popular diet of intermittent fasting that restricts eating to eight hours per day, separated by 16 hours of fasting, is not effective on its own as a means of either losing weight or for improving key metabolic health markers, according to a new study led by researchers at UC San Francisco.  ...continue reading "Intermittent Fasting Study Didn’t Find Expected Health Benefits"

Want to lose weight without counting calories?  According to a recent study, weight loss occurs easily in people only eating during a time-restricted time (a limited time each day). Eat all you want, but only during a 4 or 6 hour time period, and then no food the rest of the day. Drink plenty of water, and during fasting hours can also drink zero calorie beverages (black coffee, tea, diet soda).

The study found that two groups of obese adults who only ate within a 4 or 6 hour period each day had a similar weight loss over a 2 month period, similar reductions in insulin resistance and oxidative stress, and resulted in similar body fat loss. Eating within this short time (either 4 or 6 hours) actually resulted in consuming about 550 fewer calories per day.

On average, participants were 47 years old, weighed about 220 pounds (100 kg) and with a body mass index (BMI) of 37 at the start of the study. Most were women (90%) and about 66% were Black. After 8 weeks, persons in both the 4 and 6 hour eating period lost about 3.2% of their initial weight, while those in the control group (who continued eating normally) lost 0.1% of their starting weight.

Can you do it? One example - only eat lunch and dinner every day, say between noon and 6 pm, and watch those pounds melt off! It'll be tough to not eat at other times, but hey! - it's eat what you want (even though you'll ultimately eat less each day), no calorie counting, and still lose weight!

Excerpts from Medscape: Time-Restricted Feeding a 'Viable Option' to Lose Weight

Adults with obesity had similar weight loss and improvements in some cardiometabolic markers after restricting their eating to 4 or 6 hours a day for 2 months, in a new study. ...continue reading "How to Lose Lose Weight Without Counting Calories"

Another great option for losing weight and better health may be to only eat within a 10 hour window, and then not eat for 14 hours (thus a nightly 14 hour fast). Many may find this easier than traditional dieting (counting calories and restricting eating). Just eat breakfast later, supper earlier, and no snacks in the evening. (But water is OK.)

Researchers from the Univ. Of California and Salk Institute conducted the 10-hour restricted eating study on persons with metabolic syndrome, most of whom were also on high blood pressure (anti-hypertensive) medicine and statins. After 12 weeks the people had lost weight, lost body fat, lowered blood pressure, reduced cholesterol, and decreased the size of their waist.

Since metabolic syndrome raises the risk for diabetes and heart (cardiovascular) disease, then 10-hour restricted eating can be an important tool to improve health. The researchers point out that in animal studies, time-restricted feeding can prevent and reverse aspects of metabolic diseases, and in healthy humans, it reduces the risks of metabolic diseases. Studies also found benefits with 9-hour restricted eating and 12 hour fasts.

From Science Daily: Clinical study finds eating within 10-hour window may help stave off diabetes, heart disease  ...continue reading "Improve Health and Lose Weight By Restricting Eating To A 10 Hour Window"

Evidence is growing that "mini-fasts" (when food is not eaten) for as little as a 12 hour time period every day is good for the body and may help with weight control. For example, eat supper and then nothing more (but water is OK) till the next day's breakfast - instant 12 hour fast! The second study posted liked a 16 hour mini-fast. From the NY Times:

A 12-Hour Window for a Healthy Weight

Scientists, like mothers, have long suspected that midnight snacking is inadvisable. But until a few years ago, there was little in the way of science behind those suspicions. Now, a new study shows that mice prevented from eating at all hours avoided obesity and metabolic problems — even if their diet was sometimes unhealthful.

Researchers at the Salk Institute for Biological Studies in San Diego and elsewhere began experimenting with the eating patterns of laboratory mice in a previous study. On that occasion, some mice consumed high-fat food whenever they wanted; others had the same diet but could eat only during an eight-hour window. None exercised. The mice that ate at all hours soon grew chubby and unwell, with symptoms of diabetes. But the mice on the eight-hour schedule gained little weight and developed no metabolic problems. Those results were published in 2012.

For the new study, which appeared in the journal Cell Metabolism in December, Salk scientists fed groups of adult males one of four diets: high-fat, high-fructose, high-fat and high-sucrose, and regular mouse kibble. Some of the mice in each dietary group were allowed to eat whenever they wanted throughout their waking hours; others were restricted to feeding periods of nine, 12 or 15 hours. The caloric intake for all the mice was the same.

By the end, the mice eating at all hours were generally obese and metabolically ill, reproducing the results of the earlier study. But those mice that ate within a nine- or 12-hour window remained sleek and healthy, even if they cheated occasionally on weekends. What’s more, mice that were switched out of an eat-anytime schedule lost some of the weight they had gained.

“Time-restricted eating didn’t just prevent but also reversed obesity,” says Satchidananda Panda, an associate professor at the Salk Institute who oversaw the studies. “That was exciting to see.” Mice that consumed regular kibble in fixed time periods also had less body fat than those that ate the same food whenever they chose.

Precisely how a time-based eating pattern staved off weight gain and illness is not fully understood, but Dr. Panda and his colleagues believe that the time at which food is eaten influences a body’s internal clock. “Meal times have more effect on circadian rhythm than dark and light cycles,” Dr. Panda says. And circadian rhythm in turn affects the function of many genes in the body that are known to involve metabolism.

To date, Dr. Panda’s studies have been conducted with only mice, but he says the results seem likely to apply to humans. The upshot: Contain your eating to 12 hours a day or less. And pay attention to when you begin. The clock starts, Dr. Panda says, with “that first cup of coffee with cream and sugar in the morning.”

Another article also liked an "energy restriction period" (mini-fast), but they liked a 16 hour non-eating period.Here is the complete abstract (summary) of the article in Proceedings of the National Academy of Sciences USA,Nov. 25, 2014:

Meal frequency and timing in health and disease.

Although major research efforts have focused on how specific components of foodstuffs affect health, relatively little is known about a more fundamental aspect of diet, the frequency and circadian timing of meals, and potential benefits of intermittent periods with no or very low energy intakes. The most common eating pattern in modern societies, three meals plus snacks every day, is abnormal from an evolutionary perspective. Emerging findings from studies of animal models and human subjects suggest that intermittent energy restriction periods of as little as 16 h can improve health indicators and counteract disease processes. The mechanisms involve a metabolic shift to fat metabolism and ketone production, and stimulation of adaptive cellular stress responses that prevent and repair molecular damage. As data on the optimal frequency and timing of meals crystalizes, it will be critical to develop strategies to incorporate those eating patterns into health care policy and practice, and the lifestyles of the population.