Live Longer Habits

Intermittent fasting is a way of eating that alternates between periods of not eating and times when you do eat. Research suggests that this approach can help with weight management and may even help reverse some health issues. But how exactly does it work, and is it safe for everyone? 

What is Intermittent Fasting? 

Unlike most diets that focus on what you should eat, intermittent fasting is all about when you eat. During fasting periods, you avoid food altogether, while during eating windows, you enjoy meals. Studies have shown that fasting for certain hours each day or having just one meal a couple of times a week can be good for your health. 

Mark Mattson, a neuroscientist with 25 years of experience in this area, explains that our bodies are built to go for long stretches without food. In ancient times, before farming, people were hunters and gatherers who needed to survive without constant access to meals. They had to work hard to find food, which meant going without eating for a while. 

Experts point out that maintaining a healthy weight was easier 50 years ago. Back then, people didn't have computers and TV shows often ended at night, so many folks stopped eating when they went to bed. Portion sizes were smaller, and people were more active—spending time outside for work and play. 

Today, with entertainment available around the clock, people—including children—often stay up late watching shows, scrolling through social media, or playing video games. This can lead to eating more frequently and less movement overall. Eating extra calories with less activity can raise the risk of health problems like obesity, type 2 diabetes, and heart disease. Some scientific studies suggest that intermittent fasting could help reverse this trend. 

How Does Intermittent Fasting Work? 

There are different ways to do intermittent fasting, but all of them involve designating specific times to eat and fast. For example, you might eat for eight hours during the day and fast for the remaining 16 hours. Alternatively, you could eat just one meal a day on two days of the week. There are many options to choose from. 

Mattson explains that after fasting for a while, your body will use up its sugar reserves and start burning fat for energy. He calls this “metabolic switching.” Most people eat throughout the day, which means they rely on these calories and don’t burn much fat. Intermittent fasting allows your body more time to switch from burning food to burning fat, which may help with weight loss. 

Intermittent Fasting Plans 

Before starting intermittent fasting, it’s crucial to talk to your doctor. Once you get the green light, it's quite easy to begin. 

One common approach is the 16/8 method, where you eat for eight hours and fast for 16 hours each day. While some research suggests this method can work well for some, other studies have shown that limiting your eating windows alone doesn’t guarantee weight loss. 

Another plan is the 5:2 method, where you eat normally for five days and limit yourself to one smaller meal (about 500-600 calories) on the other two days. For example, you could have a regular diet from Sunday to Friday, with just one meal on Mondays and Thursdays. 

Longer fasting periods—like 24, 36, or even 72 hours—aren't necessarily more beneficial and can be risky. Extended fasting might prompt your body to store more fat due to perceived starvation. 

Mattson notes that it typically takes two to four weeks for your body to get used to intermittent fasting. You might feel hungry or irritable at first, but those who stick with it often report feeling better. 

What Can I Eat While Intermittent Fasting? 

During fasting times, you can drink water and unsweetened beverages like black coffee or tea. However, eating “normally” doesn’t mean indulging in unhealthy foods. Research suggests that loading up on junk food during your eating windows won’t lead to weight loss or better health. One of the benefits of intermittent fasting is the flexibility it offers regarding food choices. 

Experts recommend a Mediterranean diet as a solid choice. This diet includes plenty of leafy greens, healthy fats, lean proteins, and whole grains, and is widely regarded as a nutritious way to eat. 

Benefits of Intermittent Fasting 

Research shows that the fasting periods provide more than just fat-burning benefits. Mattson explains that these metabolic changes positively affect both the body and brain. A study published in the New England Journal of Medicine highlighted several health benefits, such as a longer lifespan, leaner bodies, and improved mental clarity. 

Some key benefits include: 

- Improved Thinking and Memory:

Studies show intermittent fasting can enhance memory and cognitive function. 

- Better Heart Health: 

Fasting can lead to healthier blood pressure and heart rate. 

- Physical Performance:

Young men who fasted for 16 hours lost fat while keeping their muscle mass. Animal studies revealed that alternate-day feeding improved endurance. 

- Weight Management: 

Animal studies indicate that intermittent fasting can prevent obesity. Some studies suggest disadvantaged adults may experience weight loss with this method, and it can also improve conditions like type 2 diabetes. 

- Better Tissue Health: 

Animal research shows that fasting can lower tissue damage during surgery. 

Is Intermittent Fasting Safe? 

Some people use intermittent fasting for weight control, while others turn to it for managing ongoing health issues like high cholesterol or irritable bowel syndrome. However, intermittent fasting may not be suitable for everyone. 

Before starting any new eating plan, including intermittent fasting, it’s best to consult with your doctor. 

Some groups should avoid this method, including: 

- Children and teenagers under 18 years. 

- Pregnant or breastfeeding women. 

- People with type 1 diabetes who take insulin, as fasting could lead to unsafe drops in blood sugar. 

- Those with a history of eating disorders. 

For those who do not fall into these categories and can safely practice intermittent fasting, it can be a beneficial lifestyle change. Just remember that intermittent fasting may affect everyone differently. If you experience unusual feelings such as anxiety, headaches, or nausea after starting, talk to your doctor.

Source: hopkinsmedicine