Have you heard of intermittent fasting? It’s been popular over the last few years as a way to lose weight, but research shows it may have some anti-aging benefits too.
What is Intermittent Fasting?
Intermittent fasting is like any other fast—it involves a period of going without food. The “intermittent” part means you go without food intermittently—from time to time. How often and for how long is completely up to you.
That’s the beauty of this diet—it’s highly flexible. When you’re just starting, you may choose to go eight hours a day without eating. That’s easy for most people as we already do it while we’re sleeping. You don’t eat between midnight and 8:00 the next morning, for instance. This is why the first meal of the day is called “breakfast,” as you are “breaking the fast” you were in overnight.
Of course, to lose weight and experience some of the other benefits of intermittent fasting, you need to go longer than eight hours. Most beginners start with 12 hours. So you would stop eating at 8:00 at night, and not eat again until 8:00 the next morning. This sort of fast is manageable, as you simply make sure to be done eating dinner by 8:00 at night, then you refrain from snacking the rest of the night and enjoy a full breakfast the next morning.
Some people do more. They go for 16 hours between eating periods, for example. But you don’t have to go that long to experience better health.
What are the Health Benefits of Intermittent Fasting?
Fasting isn’t new. For thousands of years, people have fasted for a variety of reasons, health being one of the main ones. In fact, fasting is one of the oldest therapies in medicine and has long been used to encourage the body to heal itself.
Modern research has confirmed that fasting can provide significant health benefits as long as it’s managed correctly. Extreme fasting can cause problems like dehydration and nutrition deficiencies, but intermittent fasting can be good for the body.
When we stop eating for a time, the body undergoes several changes. Hormone levels change to make stored fat more accessible for energy. Insulin levels drop, which encourages fat burning. Cellular repair accelerates, and changes occur in our genes that help protect against disease. More specifically, studies have found that intermittent fasting can have the following benefits.
1. Weight Loss
A 2015 review of 13 studies on intermittent fasting found that any version of intermittent fasting may contribute to weight loss. The average weight lost ranged from 1.3 percent for a two-week trial to 8 percent for an eight-week trial.
A second review of 40 studies also found that intermittent fasting was effective for weight loss, with a typical loss of 7-11 pounds over 10 weeks.
2. Heart Health
Intermittent fasting may help boost cardiovascular health by having a positive effect on both blood cholesterol and blood pressure levels. In one three-week-long study, researchers found that alternate-day fasting helped lower total cholesterol and LDL “bad” cholesterol when done in combination with endurance exercise.
Studies have also shown that intermittent fasting helps lower blood pressure as well as heart rate. Unfortunately, the effects lasted only as long as the diet did.
3. Brain Function
Early animal studies suggested that intermittent fasting may help protect against age-related memory decline. Later human studies seemed to confirm this benefit. Fasting seems to increase synaptic plasticity (a marker of learning and memory), enhances performance on memory tests, and leads to the growth of new neurons in the brain. It may also help decrease the risk of diseases like Alzheimer’s disease.
4. Blood Sugar
Studies show that intermittent fasting can help stabilize blood sugar levels in people with diabetes, as it helps to reset insulin. In one 2017 study, for instance, scientists found that short-term daily intermittent fasting helped improve body weight and blood glucose levels.
It also improves insulin resistance, which can reduce the risk of developing type 2 diabetes in the first place. In a 2019 study, researchers found that intermittent fasting improved insulin sensitivity.
Might fasting help you live longer? Some studies seem to suggest it’s possible, finding that periods of fasting might promote healthy aging, improving cellular function and metabolism.
In 2018, a group of scientists from the National Institute on Aging found in an animal study that increasing time between meals improved overall health and lengthened life. Bonus: it didn’t matter what the mice ate or how many calories they consumed during the eating periods—the benefits still held.
In a 2019 study, scientists found similar results—that eating in a 6-hour period and fasting for 18 hours could trigger a metabolic switch from glucose-based to ketone-based energy, with increased stress resistance and longevity, and a decreased risk of diseases like cancer and obesity.
How Intermittent Fasting Can Slow Aging
It’s this “anti-aging” effect of intermittent fasting that intrigues beauty enthusiasts. Considering all the benefits listed above, we can see how intermittent fasting could be good for overall health, which is going to help you look and act younger anyway. But there’s more to it.
1. Reduced Inflammation
For one, intermittent fasting can reduce inflammation, and that’s great for delaying the appearance of aging. Inflammation is behind all those wrinkles, sagging, bagging, redness, and other flaws. Since we are particularly susceptible to inflammation in our world today—because of poor diet and stress—it’s likely that many of us are dealing with chronic inflammation.
Researchers have found that short-term fasting reduces inflammatory activity and improves chronic inflammatory diseases.
2. Healthier Cells
Cells tend to be healthier in people who fast regularly. The practice reduces cellular damage and helps maintain healthy DNA—both of which can delay aging and keep the skin looking and acting healthier over time.
Indeed, fasting daily has been found to help increase resilience to oxidative stress, and since oxidative stress is behind most types of skin damage, it makes sense that this would result in stronger, healthier skin.
3. Younger Appearance
We don’t have a lot of research on intermittent fasting and appearance yet, but there is some evidence that it may help improve skin health.
In 2019, for instance, researchers reviewed the scientific literature and reported that fasting was associated with increased wound healing, decreased damage to skin proteins like collagen, and even reduced side effects associated with topical retinoid treatment. Also, some studies have found that fasting can help improve symptoms related to skin diseases like eczema, psoriasis, and acne.
How to Get Started with Intermittent Fasting
If you’re convinced and want to try intermittent fasting yourself, always talk to your doctor first. Then try these tips:
You don’t have to fast for a full day. Start with 12 hours and build it around the hours you usually sleep to make it easier.
Choose the best program for you.
Once you have gotten used to fasting in 12-hour periods, you may want to consider stepping it up a little. Options include:
- 16-8 Fast: Eat during an 8-hour period, then fast the other 16 hours. You can do this 2-3 times a week, or every day—whichever works best for you. You can also set your 8-hour eating period whenever you want.
- 20-4 Fast: Similar to the fast above, except you shorten your eating period to only 4 hours, then fast for 20.
- Once per week: Eat normally six days of the week. On the sixth day, have lunch, then fast until lunch the next day, for a full 24 hours. You can also go from dinner to dinner if you like.
- Once per month: Follow the example above for a 24-hour fast, but do it only once a month rather than once a week.
- 5:2 Fast: This form of fasting has significant scientific support behind it. You eat normally for 5 days of the week, then fast for two days of the week. You choose whatever days you like. During the two fasting days, you eat only 500 calories. You can eat them anytime during the day, either spread out or at a single meal.
Consider your timing.
Scientists have found that when you fast may be more important than how long you fast. Restrict your eating periods to earlier in the day and you’ll likely experience better weight-loss and other benefits. In one study, for example, researchers compared two groups:
- One fit all their meals into eight hours from 7:00 a.m. to 3:00 p.m.
- Another spread their meals out over 12 hours, from 7:00 a.m. to 7:00 p.m.
Both groups maintained their weight, but after five weeks, the eight-hour group had dramatically lower insulin levels and significantly improved insulin sensitivity, as well as significantly lower blood pressure. They also had significantly decreased appetite.
These results show that the earlier you stop eating in the day, the better your results are likely to be.
It’s important to stay hydrated always, but particularly during fasting periods. Drink water regularly and feel free to indulge in coffee and tea as needed. Peppermint is a good option—it’s known to reduce appetite.
Eat more protein.
During your eating periods, be sure you’re getting enough protein. It will keep you satisfied longer and help you avoid cravings.
Listen to your body.
If your stomach is growling and you’re thinking about food, distract yourself with another activity and it will pass. If you’re feeling dizzy or fatigued, however, or if you just don’t feel “right,” listen to your body. It may be time to eat something. Start small and go for a protein-rich snack.
Have you tried intermittent fasting?
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