What Is The Best Diet For You? Reviews Of Diets

In recent years, intermittent fasting has become a popular dietary protocol.

Fasting is not a new trend. It has been part of many cultures and religions around the world for centuries.

Fasting may be beneficial for your health in many ways, including reducing hunger, improving insulin sensitivity, and lowering blood pressure.

Intermittent fasting is not suitable for all lifestyles and fitness goals, despite its benefits.

How can you decide if intermittent fasting will work for you?

Continue reading our Diets Reviewed Series for more information on intermittent fasting.

What is intermittent fasting (IF)?

Fasting can be defined as abstaining from food or beverages for varying periods of time, ranging from a few hours per day to several weeks[1],[2]. There is no clinically defined time when fasting starts after eating or drinking, but it’s a lifestyle that seems to improve many chronic non-infectious illnesses[3],[4].

The intermittent fasting method involves not eating for a certain period of time during the day or week. All types of fasting have one thing in common: energy restriction.

There are three different types of intermittent fasting:

1. Intermittent calorie restriction

This fasting method, also known as whole-day or extended fasting involves fasting over 24 hours twice or three times per week. On days when they are not fasting, the observers may eat as much as they want. As much as you want. After a fasting cycle, it is common to have at least a week of normal eating[5].

Two sub-types of intermittent calorie restriction are possible:

• The 2:5 Method: restricting calories for two days, followed by a five-day period of normal eating.
• The 3:4 Method: restricting calories for three days followed by four days of normal eating.

It’s not unusual for protocols to allow up to 25% of daily expenditure during fasting days. This works out as 400-600 kcal per day[6].

2. Alternate Day Fasting (ADF).

ADF is a method that has become increasingly popular. It involves alternately eating ad-libitum on non-fasting and fasting (usually under 500 kcal) days. Some ADF methods do not allow any caloric consumption on fasting day. [9]

3. Time-restricted Feeding (TRF).

TRF is a method that involves daily periods of complete fasting. Eating is only allowed outside these hours. TRF can be divided into three types:

• 16:8 – 16 hours fasting followed by a feeding window of eight hours.
• 18:6 – 18 hours of fasting followed by a 6-hour feeding window.
• 20:4 – 20 hours of fasting followed by a feeding window lasting four hours[10].

Ramadan is a period of fasting in the Islamic calendar that lasts for the entire ninth month. It also falls under TRF. Observing Muslims refrain from eating and drinking between dawn and sundown, which can vary depending on the season and geographical location. However, in general, this fast lasts 18 hours[11].

The research on ‘chrononutrition’ has led to the idea that TRF can have a number of benefits. This is because the timing of meals and the circadian rhythm of the body, which controls human physiology and metabolism, are closely linked[12]. The metabolic benefits of TRF are thought to be due to a better alignment with the natural pattern for feeding and fasting that is found in many organisms who have a circadian clock[13].

These three approaches differ in terms of the restriction on calories, the amount and frequency of fasting, as well as the food or drinks allowed. Most TRF methods involve fasting a certain period of time, like 16 or 20 hour, which reduces the eating window. ADP involves alternating fasting and eating days.

What is the intermittent fasting?

Fasting appears to be a good lifestyle strategy for managing chronic non-infectious illnesses[14]. This includes conditions that are classified as’metabolic diseases’, including type 2 diabetes and cardiovascular disease (CVD). Fasting can have many health benefits, including improving blood lipids, insulin sensitivity, and blood pressure without weight loss.

This finding may be explained by the fact that fasting causes a coordinated series of metabolic changes which allow the body’s energy to become more dependent on fat and less on carbohydrates[18]. This phenomenon is known as “metabolic switching” and occurs when glucose levels are elevated for six hours following a meal, before dropping for 16 hours. The amount of insulin in circulation decreases, while the levels of ketones and free fatty acids (a substance that is produced by your body when there is not enough insulin to turn glucose into energy) increase[19]. Intermittent fasting may be a good option for people who want to improve insulin sensitivity but struggle with a low carbohydrate diet.

But, there is plenty of evidence that shows weight loss (which can be achieved in multiple ways) to be the best predictor of increased insulin sensitivity. This improves when you engage in regular physical activity[20]. Fasting can reduce calorie consumption while increasing satiety. You can reduce the time between meals by reducing your eating window. If you are on a calorie controlled diet, IF can help you to feel less hungry and increase weight loss.

Along with weight loss, exercise and physical activity, fasting can improve insulin sensitivity.

Claims in the spotlight

In recent years, intermittent fasting has been a hot topic of discussion. Which of these claims are you willing to believe and which ones should you be skeptical about?

1. “Intermittent fasting boosts weight loss .’

ADF is beneficial for weight loss and fat mass reduction[21],[22]. Observational studies show that women and obese individuals tend to experience greater weight loss and changes in body fat percentage after fasting. This is true regardless of calorie intake[23],[24]. Other evidence, however, shows that the average weight loss outcome is similar for both IF and continuous energy restriction[25]. It’s more likely that the benefits of intermittent fasting come from its ability reduce energy intake on average across the week, rather than any special ‘fat-burning’ effects.

2. ‘Intermittent Fasting Improves Metabolic Health .’

Metabolic disease is characterized by insulin resistance and high blood sugar levels. Together, they create a deadly cocktail that can lead to CVD and atherosclerosis. They also damage the beta cells in the pancreas which are crucial for insulin production [26],[27],[28]. In order to keep blood sugar levels from rising dangerously, type 2 diabetics who are very advanced often need insulin injections.

The health benefits of IF are not without substance, as the evidence shows that it has a positive impact on these markers. The majority of IF research focuses early time-restricted eating, limiting food intake to a 4-to-8-hour window early in the day. Fasting for the remainder of the day (8 am – 4:00 pm). It has been shown that this method can lower blood pressure, improve insulin resistance, and restore beta cells in diabetics without weight loss or caloric restriction[29],[30]. This fasting variation lowered blood-pressure as much as the gold standard medications in one study[31].

Losing around 10% of your total body weight seems to have the same positive effect [32]. While IF may have a slight advantage over other methods, it is not the only one.

3. “Intermittent fasting can cause muscle loss .’

Although IF can improve fat oxidation, insulin sensitivity and body composition, insulin also plays a vital role in the body’s ‘anti-catabolic function’. Preventing tissue breakdown. The circulating level of amino acids is critical in preventing muscle tissue breakdown. These amino acids are primarily derived from protein consumption.

Resistance training increases the body’s constant state of “turning over” muscle tissue by breaking down old proteins and synthesizing new ones. Protein synthesis, a metabolic process highly dependent on our nutritional environment has a significant impact on muscle quality and health[33]. Resistance training and protein intake are the primary signals to the body during periods of caloric restrictions to maintain lean body mass. Fasting is not optimal for maintaining or enhancing muscle mass because it involves long periods of time without food.

Further research has revealed that where muscle loss is increased due to IF it’s due to the severity and speed of the deficit as well as a reduced intake of total protein[35],[36]. If you don’t plan to compete in the Olympia, your muscle loss should not be an issue as long as you are eating enough calories and protein for your body composition and goal.

When following a fasting regimen, resistance training and protein intake are the main ways to signal the body to maintain lean muscle.

Pros and cons of intermittent fasting

1. IF can reduce hunger

People often feel fuller after intermittent fasting, according to research[37]. It is possible that this is due to a decrease in the circulating levels of ghrelin – a hunger hormone. This seems to happen independently of weight loss[38]. IF is also beneficial for managing hunger because it reduces the time between meals. If you have trouble staying away from the refrigerator, IF may help.

2. IF helps you to reduce your calorie consumption without weighing or tracking.

Researchers have found that people can reduce their caloric intake by up to 20% without changing their diet. It is possible that IF’s satiating effect reduces the risk of overeating after the fast, thereby eliminating a net deficit. IF is a good option for those who do not enjoy tracking calories. Remember that the most important factor in weight loss is energy balance. So even if tracking calories is not your thing, you should still make sure you are burning more than you consume.

3. IF can be useful if your mornings are busy

The priority of meal timing is ranked behind the total daily caloric intake, protein consumption and nutritional density[41]. If you are not an elite athlete, then it will make little difference to your fat loss if you consume all of your calories at once or spread them out over 10 meals. If you’re on a tight schedule, like a morning workout or dropping your kids off at school, you may want to eat your first meal a little later. You will feel more satisfied and less stressed in the morning.

4. If you suffer from high blood pressure or diabetes, or have high cholesterol, IF may be beneficial.

IF is proven to improve insulin sensitivity, lipid profile and blood pressure[42],[43],[44]. Fasting can help you improve your health if you’ve been diagnosed with one of these conditions. Remember that your first priority should be to improve your body composition. Choose the method that allows you to achieve this consistently and for a long time.

Fasting is proven to improve insulin sensitivity, blood pressure and lipid profiles.

Cons of intermittent fasting

1. IF might not be right for your lifestyle and preferences

Even the best diet plan is worthless if you cannot stick to it. If you are someone who likes to eat as soon as you wake up in the morning or have trouble going long periods without food, IF is not for you.

2. IF can impact on training performance

What you eat during your training window may impact strength, muscle growth and training performance[45],[46],[47]. Remember that the macronutrient breakdown and total energy intake are the primary determinants of recovery and growth. If you decide to fast, it’s important that your training doesn’t fall in the middle.

3. IF can negatively impact female hormonal health

Some studies have shown that fasting may increase the risk of menstrual disorder[48],[49]. If you suffer from hormonal imbalances or an irregular cycle, IF may not be the best option for you.

4. IF is effective for fat loss but can make muscle building phases more difficult.

Dieting can be made easier by intermittent fasting, which has a positive effect on appetite management and calorie intake. If you are in a calorie excess and following a phase of muscle gain, IF can make it difficult to eat the calories needed for growth.

Fasting may affect your performance at the gym.

What you need to know about intermittent fasting

Evidence shows that intermittent-fasting methods are effective in improving weight loss strategies and generating improvements to health markers. It’s crucial to realize that the application of any diet is what determines its success. If intermittent fasting suits your lifestyle and preferences, then it may help you achieve your goals. If you don’t want to go for long periods of time without eating, there are other ways that are equally effective in improving your long-term health.

The Key Takeaways

• The intermittent fasting protocol (IF) involves abstaining for a specific period from eating or drinking.
• Ramadan fasting, for example, is a type of intermittent fasting. Other types include alternate-day fast, intermittent caloric restriction and time-restricted eating.
• Through its effects on insulin sensitivity, blood lipids and blood pressure, fasting can have a positive impact on metabolic health without affecting weight loss.
• Fasting can help you achieve a calorie deficit by improving your appetite and satiety.
• IF has its benefits, but other methods can produce similar results if IF doesn’t suit you or your lifestyle.