How Can Intermittent Fasting Decrease the Risk of Chronic Health Conditions?

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Many diets and eating plans focus on what to eat, but intermittent fasting (also called time-restricted eating or TRE) is an eating plan that focuses on when you eat. With intermittent fasting, you only eat within a specific timeframe. Research has shown that intermittent fasting isn’t only helpful for weight loss, but that it can also decrease the risks of metabolic syndrome.

One recent study found that participants who reduced their eating hours from a 14-hour window to a 10-hour window lost an average of 7 lbs. over 12 weeks. They were also able to reduce their waist circumference by an average of about 4 cm and saw improved blood parameters. The participants could eat as much as they wanted and weren’t limited to any particular foods; despite this, each of them ate approximately 200 fewer calories per day. Although there was no control group, the results of this study and many others suggest intermittent fasting is a potentially powerful eating plan that can benefit weight and prevent (or even reverse) some health conditions.

What is Metabolic Syndrome?

Metabolic syndrome is a group of five health conditions that can lead to heart disease, type 2 diabetes, stroke, and other serious health problems. Metabolic syndrome is diagnosed when an individual has three or more of the following risk factors:

  • High blood pressure
  • High blood glucose (sugar)
  • Low levels of HDL (good) cholesterol
  • High levels of triglycerides
  • A large waist circumference or “apple-shaped” body

Each of these conditions is a risk factor for cardiovascular disease, but when someone has three or more, the chances of developing serious cardiovascular problems increase. The underlying causes of metabolic syndrome include being overweight or obese, insulin resistance, physical inactivity, genetic factors, and age. Although metabolic syndrome is a serious condition, the risks can be significantly reduced through weight loss, regular exercise, intermittent fasting, and a healthy diet.

Types of Intermittent Fasting

According to John Hopkins neuroscientist, Mark Mattson, our bodies have evolved to go without food for anywhere from hours to even several days. Mattson, who’s studied intermittent fasting for 25 years, says the eating plan is similar to how humans would have eaten during prehistoric times. Before we discovered how to farm, humans were hunter-gatherers who would go long periods without eating while they searched for food.

John Hopkins dietitian Christie Williams, M.S., R.D.N., says that it was easier for people to maintain their weight just 50 years ago because people were less sedentary overall. There were no computers, no 24/7 streaming services, or smart phones; T.V. shows stopped airing at 11 pm and people stopped eating earlier (rather than late-night snacking) because they went to bed earlier. Portions were also much smaller than what many people eat today.

In some ways, intermittent fasting could be seen as a more natural way to eat. There are several different types of intermittent fasting, but all of them involve eating very little or nothing at all during the fasting period; water, coffee, and other calorie-free beverages are allowed.

Here are three of the most popular methods:

  • Time-restricted eating

This method involves fasting every day for 12 hours or longer. One of the most popular methods, the 16/8 method, involves skipping breakfast and restricting your eating period to 8 hours each day and then fasting for 16 hours. For example, your eating period might be from 12 pm to 8 pm, followed by a 16 hour fast.

  • Eat-Stop-Eat

This method involves fasting for a full 24 hours once or twice a week.

  • 5:2 diet

With the 5:2 diet, you would consume 500-600 calories for two non-consecutive days each week, then eat normally the other five days.

Many people find the 16/8 method to be the easiest to stick with. Although intermittent fasting is considered safe for most people, it’s best to discuss it with a healthcare professional before altering your diet, especially if you take certain medications or are diabetic.

The Health Benefits of Intermittent Fasting

Regardless of the intermittent fasting method used, numerous studies have shown that following the eating plan can have powerful benefits for your body, as well as your brain. Not only can it help you lose weight, but animal and human studies also suggest it can improve overall health and even help you live longer. Here are eight evidence-based benefits of intermittent fasting:

  1. Changes to how hormones, cells, and genes function

When you fast, it changes the way your hormones, cells, and genes function:

  • Blood insulin levels drop significantly, which enables fat burning
  • Blood levels of human growth hormone may increase dramatically, allowing for fat burning, muscle gain, and other benefits
  • The body starts important cellular repair processes, like removing waste from the cells. This process, known as autophagy, may also offer protection against several diseases, including cancer and Alzheimer’s disease.
  • Beneficial changes in several genes and molecules related to disease protection and longevity
  1. Weight loss and reduction of visceral fat

Unless you’re offsetting missed meals by eating more than you normally would, intermittent fasting generally helps you take in fewer calories. Eating fewer calories combined with positive hormonal changes (like lower blood sugar, higher HGH levels, and increased amounts of norepinephrine) increases the breakdown of body fat and helps the body use it for energy. Short-term fasting also increases metabolic rate, making it easier to burn more calories.

According to one scientific review in 2014, intermittent fasting can cause significant weight loss over 3 to 24 weeks—up to 8%. The participants were also able to lose 4-7% of their waist circumference over 6 to 24 weeks, indicating that they lost a good amount of unhealthy visceral (abdominal) fat.

  1. Reduced insulin resistance and lower risk of type 2 diabetes

Insulin resistance occurs when the cells in your muscles, fat, and liver don’t respond well to insulin. Since the glucose in the blood can’t be used for energy, the pancreas compensates by making more insulin. Over time, this causes blood sugar levels to go up and increases the risk of developing type 2 diabetes. In human studies, intermittent fasting has been shown to reduce blood sugar levels in pre-diabetic patients by 3 to 6% over an 8- to 12-week period. However, one study from 2005 suggests that intermittent fasting may have more of an impact on men than on women.

In another study, researchers looked at how intermittent fasting affected diabetic mice and found that they had improved survival rates as well as protection against diabetic retinopathy, a complication of diabetes that can lead to blindness. This suggests intermittent fasting may have protective properties for those who are at risk of developing type 2 diabetes.

  1. Reduced oxidative stress and inflammation

Oxidative stress occurs when there’s an imbalance between free radicals and antioxidants in your body. Free radicals react with proteins, DNA, and other molecules in the body and damage them. There’s a fair amount of scientific evidence suggesting that oxidative stress contributes to the development of chronic conditions, like cancer, diabetes, and heart disease, as well as the aging process. Several studies have shown that intermittent fasting may increase the body’s resistance to oxidative stress as well as inflammation—another cause of many common diseases.

  1. May improve heart health

Heart disease is the most common cause of death worldwide. Intermittent fasting has been shown to improve several different risk factors for heart disease, including blood sugar, blood pressure, triglyceride levels, total and LDL (bad) cholesterol, and inflammatory markers.

  1. May prevent cancer

Animal studies have provided promising evidence that intermittent fasting may help prevent cancer. Some human research has led to similar results, however, more research is needed to make a determination. There’s also evidence that fasting may reduce some of the side effects of chemotherapy.

  1. Cognitive benefits

Intermittent fasting has been shown to improve various metabolic features that are essential to brain health; it’s also been shown to increase levels of a hormone called brain-derived neurotrophic factor (BDNF). BDNF deficiencies have been thought to play a role in depression and other brain conditions including Huntington’s, Alzheimer’s, and Parkinson’s diseases. Several animal studies have suggested that intermittent fasting may also increase the growth of new nerve cells and protects the brain from damage during strokes.

  1. May increase longevity

Intermittent fasting has been shown to increase the lifespan of several different species during animal studies, including rats, mice, and fruit flies. Some of the results were quite dramatic in some of the studies; in one study, rats that were fasted every other day live 83% longer than rats in the control group. Daily fasting also led to improved overall health in male mice and delayed the onset of two common diseases in aging mice (fatty liver disease and hepatocellular carcinoma).

Get Your Health Back on Track with Intermittent Fasting

Although intermittent fasting has become very popular as a weight-loss method, there’s growing evidence that its benefits extend far beyond weight alone. Although more human research is needed, previous studies suggest that it can have a significant impact on overall health and the aging process. Since there are many ways to practice intermittent fasting, it’s important to find a method that you find sustainable. Likewise, it’s also important to work closely with your doctor to ensure the method you choose is safe and won’t interact with medications or blood sugar levels (if you’re diabetic).

If you’re interested in starting intermittent fasting, contact Dr. Jennifer Hubert. Dr. Hubert is a board-certified physician specializing in internal medicine and medical weight loss. She focuses on the prevention and improvement of adult diseases, including high blood pressure, diabetes, heart disease, and stroke. You’ll receive a personalized health and nutrition plan with steps to take to make healthy, effective lifestyle changes that will benefit you beyond losing weight. Her wellness plans have helped hundreds of Santa Rosa residents regain their health and improve their lives. Schedule a consultation today by calling 707-575-THIN (8446).