Tag Archives: fasting

Eat slow, then fast: When and how you matter as much as what you eat for weight control.

What you eat is an essential part of achieving and maintaining good health. What you may not know is that when and how you eat can be just as important. This is especially true if your goal is to lose weight. Here are two ways to change the way you eat to help you lose weight and keep it off. This is the topic of my Health & Fitness column in the Aiken Standard this week.

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First, eating more slowly can help limit the amount of food you eat. Perhaps your mother admonished you to “slow down” at meals when you were young. This was good advice, for both practical and physiological reasons.

As an aside, your mother may also have told you to “chew your food.” too. This was probably to remind you to eat more slowly.  Almost 100 years ago Horace Fletcher recommended a process that involved chewing each bite of food 100 times. “Fletcherizing,” as it was called, was a way to reduce how much people ate, among other more dubious health claims.

Your appetite is regulated by a host of factors, including the presence of food in your stomach. As you eat, your stomach fills, triggering the release of hormones that signal your brain to reduce your appetite. The result is that as your stomach fills, you feel less hungry. Eating quickly, like many of us do, allows you to take in lots of calories before your brain gets the message that you are full.

Practically, eating slower means you will eat fewer calories during mealtime. If you slow down at meals, you start to feel full before you eat as much. Research shows that this can lead to lower calorie intake during the meal. In addition to controlling how much food you consume, eating more slowly is a good way to enjoy meals, both the food and the company, more fully.

Second, extending the time between meals or limiting eating to fewer hours per day may affect your metabolism in ways that may help with weight control. There are two main ways to incorporate fasting into your diet. Intermittent fasting involves having some days on which you don’t eat. An example is the 5:2 program, in which you include two water-only fasting days per week. While this is effective for modest weight loss and improved glucose and lipid metabolism, it isn’t easy to do.

Time-restricted feeding, in which you limit your eating to a 4 to 8 hour period each day with a 16–20 hour fast, may be easier to follow. the concept of not eating between meals, especially between dinner and breakfast, isn’t new, but research shows that having a longer fasting period each day may help you lose weight, even without counting calories.

According to a recent study, people who followed a time-restricted feeding schedule in which they were allowed to eat anything they wanted for 8 hours each day for 12 weeks. They were compared to a group that could eat whenever they wanted but were instructed to maintain their weight.

After 12 weeks, the time-restricted feeding group ate about 300 fewer calories per day, leading to a modest six-pound weight loss. By contrast, the participants who were supposed to maintain their weight did just that, with no changes in calories consumed.

This suggests that limiting eating time without focusing on calories or the specific foods eaten can lead to some weight loss. One of the biggest problems people have with changing their diet to lose weight is figuring out what to eat to reduce calorie consumption. While making dietary changes is an essential part of weight loss and weight maintenance, a good first step might be to simply limit eating time to fewer hours per day.

Even without this evidence, adopting a fasting period between dinner and breakfast, which should be about 12 hours, seems prudent. At the very least, it will keep you from snacking in the evening, which almost certainly involves unhealthy choices. And as you try to make healthier food choices, consider eating more slowly and making dinner the end of your eating day.


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Eat slow, then fast. How and when you eat may be as important as what you eat for weight control.

What you eat is an essential part of achieving and maintaining good health. What you may not know is that when and how you eat can be just as important. This is especially true if your goal is to lose weight.

My Health & Fitness column in the Aiken Standard this week describes  two ways that changing the way you eat can help you lose weight and keep it off. Neither of these are necessarily new ideas, but implementing them together may help you eat less.

First, eating more slowly can help you limit the amount of food you eat. Perhaps your mother admonished you to “slow down” at meals when you were young. This was good advice, for both practical and physiological reasons. In addition to controlling how much food you consume, eating more slowly is a good way to enjoy meals, both the food and the company, more fully.

You mother may also have told you to “chew your food.” too. This was probably to remind you to eat more slowly.  Almost 100 years ago Horace Fletcher recommended a process that involved chewing each bite of food 100 times. “Fletcherizing,” as it was called, was a way to reduce how much people ate, among other more dubious health claims.

There is a physiological reason to slow down, too. Your appetite is regulated by a host of factors, including the act of eating and the presence of food in your stomach. As you eat, your stomach fills. This triggers the release of hormones that signal your brain to reduce your appetite. The result is that as your stomach fills, you feel less hungry.

Once you start eating, it takes time for your stomach to release these hormones. Eating quickly, like many of us do, allows you to take in lots of calories before your brain gets the message that you are full. This is one factor that leads to overeating. But if you slow down at meals, you start to feel full before you eat as much. Research shows that this can lead to lower calorie intake during the meal.

Second, the time between meals may affect your metabolism in ways that result in less fat accumulation. Again, the concept of fasting between meals isn’t new, but recent research helps explain why eating less frequently may help prevent obesity and related conditions, including diabetes.

While this research was done using rats, the physiological concept may well apply to humans. In these studies, rats were put on a diet that included an overnight fast ranging from 8–12 hours. The researchers found that the rats that experienced a longer fasting period between meals had better insulin levels and less fat storage.

The reason for this seems to do with the gut microbiome, the bacteria that live in the intestine and play an important role in regulating metabolism. A longer period without food changes the nature of these good bacteria, promoting these benefits.

I first heard about this on Science Friday, which provides an excellent summary of this research.

It is unclear whether this same effect occurs in humans. Even without this evidence, adopting a fasting period between dinner and breakfast, which should be about 12 hours, seems prudent. At the very least, it will keep you from snacking in the evening, which almost certainly involves unhealthy choices.

An additional finding of this research is that the benefits of the 12-hour fast seem to persist, even through a day or two of more frequent eating. This is relevant, since many people do well to modify their eating habits during the week, but tend toward less restrained eating on the weekends. The fact that the benefits of an overnight fast most days of the week are maintained despite a “wild weekend” is good news!

The combination of what, when, and how you eat can make an important difference in how much you eat, the key to losing weight and keeping it off. As you try to make healthier food choices, consider eating more slowly and making dinner the end of your eating day.