The pervasiveness of obesity and overweight is increasing at an alarming rate worldwide. Weight loss and body composition improvement (decreasing body fat and increasing muscle mass) through physical activity, dietary guidelines, and certain modifications will help overcome obesity-related issues. While daily caloric restriction is the most prevalent form of dietary restriction, other methods are emerging. One alternative method of caloric restriction is intermittent fasting, a broad term encompassing several specific fasting protocols. Ideally, intermittent fasting comes along with periodic fasting. These programs typically lead to energy restriction, which is only sometimes maintained daily.
WHAT IS INTERMITTENT FASTING?
Intermittent fasting is an eating pattern with periodical feasting and fasting hours, which helps overcome obesity and reverse many of the comorbidities. Intermittent fasting is among the world's most popular health and fitness trends. Intermittent fasting diets are now gaining popularity as it helps in significant weight loss.
Intermittent fasting is comprehensive and circumscribes various programs that will help to manipulate the timing of eating episodes by utilizing short-term fasts to improve body composition and overall health.
Several intermittent fasting protocols have gained popularity and boast impressive anecdotal health benefits. Still, it is unlikely that all intermittent fasting regimens lead to the same physiological changes, given their different fasting and feeding patterns.
WHY FASTING?
Intermittent fasting practice that limits food consumption to daytime may impose circadian biology to improve the body's metabolic health. It has been practiced since the earliest antiquity by people around the globe. Books on ethnology and religion describe various fasting forms and practices.
Evidence is accumulating that eating for 6 hours and fasting for 18 hours can provoke a metabolic switch from glucose-based to ketone-based energy, i.e., stored fat is used as a source of energy, with increased stress resistance, endurance, and a decreased prevalence of diseases, including cancer and obesity.
According to studies, the changes in composition and metabolic function of the gut micro-organisms in obese individuals may enable an "obese microbiota" to gather more energy from the diet compared to a "lean microbiota, " thereby influencing net energy absorption, expenditure, and storage. In addition, obesity-related transformations in gut microbiota can alter gut penetrable and bacterial translocation to promote systemic inflammation, a hallmark of obesity and obesity-related diseases.
Modified fasting regimens will help in weight loss and may improve metabolic health. However, there is inadequate data to determine the optimal fasting regimen, for example, the length of the fasting gaps, the number of "fasting" days per week, energy restriction needed on fasting days, and dietary behavior on non-fasting days.
Several lines of evidence support the hypothesis that eating patterns that eliminate nighttime eating and prolonged nightly fasting intervals could improve human health and help maintain FBS levels. Prolonged night fasting may be a simple, feasible, and potentially effective strategy to prevent disease.
TYPES OF INTERMITTENT FASTING
There are many different ways to do IF, and that's great. If you're interested in doing this, approaching this fasting type will help reduce weight, change lifestyle, and prevent NCD. Here are seven:
1. 5:2 fasting
It is one of the most popular IF methods. In this type of fasting, an individual must eat five days a week without counting calories; the other two days, they have to take meager calories, i.e., 500 kcal, ideally suited for males and females.
2. Time-Restricted Fasting
You can choose an eating window daily, ideally leaving a 14- to 16-hour fasting period. Fasting promotes autophagy, which helps in clearing the debris of the body and using the stored glycogen as an energy source.
3. Overnight Fasting
This type of fasting is the simplest way of fasting up to 12 hours a day, ideally starting with 7 pm dinner at night, followers by 7.00 am breakfast in the morning. Autophagy still happens at the 12-hour mark, though you'll get more mild cellular benefits.
4. Eat Stop Eat
This type of fasting emphasizes just taking a break from food, ideally completed two days within a week.
5. Whole-Day Fasting
In this type, you eat one meal a day. Some people choose to eat dinner and then only eat the next day's dinner with whole-day fasting.
If done for weight loss, the advantage of whole-day fasting is that it's challenging (though possible) to eat one day's calorie requirement in one meal.
6. Alternate-Day Fasting
It is one of the popular approaches for weight loss. You can start with 1-day of eating and another day of fasting for 24 hours( 1-0-1). The research found that, by doing this in overweight adults, alternate-day fasting helped to reduce BMI, weight, fat mass, and total cholesterol.
7. Choose-Your-Day Fasting
It is more of a choose-your-own-adventure approach to IF. You can do time-restricted fasting (fast for 16 hours or 24 hours )every other day or once or twice a week,
*Something to remember: Researchers say that skipping breakfast has no significant effect on weight loss, so skipping breakfast may not be the ideal way to lose weight.
PROS AND CONS OF INTERMITTENT FASTING
PROS:
There have been many studies on intermittent fasting in both animals and humans. According to these studies, IF can benefit in weight loss and improve brain health.
· Weight Loss: As mentioned above, it will help you reduce weight and belly fat without reducing caloric intake.
· Insulin Resistance: Fasting can help to reduce insulin resistance. It helps to lower blood sugar and fasting insulin levels, which should protect and prevent against type 2 diabetes.
· Inflammation: Some research shows reductions in inflammation markers (CRP), a critical factor in chronic diseases.
· Heart Health: It can lower LDL cholesterol, blood triglycerides, inflammatory markers, blood sugar levels, and insulin levels. All of them are risk factors for developing heart disease.
· Cancer: Some studies have shown that the risk of cancer can be reduced by alternate-day fasting by slowing the spread of cancer cells, limiting the development of lymphoma, and limiting the survival of the tumor
· Brain Health: Fasting increases the calcineurin hormone in the brain and also helps in the growth of new nerve cells. It can also protect from and prevent the development of Alzheimer's disease
CONS:
1. Intermittent fasting requires you to go a designated period without eating. You can eat a required amount of calories in a specific window and repeat to create a caloric deficit chart. This extended period of zero calorie consumption can be problematic in the long term due to low energy levels, cravings, habits, and due to lack of discipline that is required to stick to the specific time frames of intermittent fasting.
2. Intermittent fasting is also hard to stick with long-term due to the self-control required. Both sides of intermittent fasting, i.e., the fasting and the eating window, can be challenging.
3. The majority of our social interactions occur with food and drinks. When fasting, you must either have the willpower not to indulge or figure out alternatives to still have a social life without breaking your fast.
4. Those who already lead active lifestyles or are leaner before beginning intermittent fasting may suffer from hormonal imbalances.
5. Females who do intermittent fasting will have insomnia, irregular cycles, stress, and thyroid problems.
SAFETY PRECAUTIONS FOR INTERMITTENT FASTING
1. Fasting over 24 hours leads to dizziness, lack of concentration, and loss of energy; better to avoid.
2. Maintain a well-balanced, healthy diet during your eating periods. To feel more extended, include complex carbohydrates like brown rice, lean protein, and fruits and vegetables. Watch how much food you eat during the eating periods (do not do binge eating).
3. Stay hydrated by drinking at least 8 cups of water daily (equivalent to at least two liters). Water is allowed during the fasting period.
4. Do not overexert yourself when fasting (especially during exercise)
5. If you feel unwell, stop fasting and seek medical help.
WHO SHOULD NOT DO INTERMITTENT FASTING
· Pregnant or breastfeeding women
· Patients with kidney problems.
· Patients with Liver cirrhosis
· Patients with medical conditions like hypertension and diabetes on medications should seek medical advice before performing fast.
· People with low blood pressure
· People with eating disorders like anorexia nervosa or bulimia.
· People with low BMI( underweight)