Fasting for weight loss: 7 tips to get the best from your fast

Fasting is an effective way to burn fat and lose weight, in addition to its benefits to health and lifespan. However, going against the body’s natural instinct to eat can seem impossible. Follow these tips to optimise your fast every day of the week.

What is fasting?

Fasting is the ancient practice of restrictive eating that can be used to lose weight through the process of ketosis, which metabolises fat reserves. It has become the most popular diet method in the US, according to the International Food Information Council’s 2020 annual Food and Health survey [1]. Caloric restriction additionally offers numerous health benefits; for example, by stimulating cellular nutrient stress, fasting triggers autophagy (Ancient Greek for ‘self-eating’), a process by which damaged cells are rejuvenated. Hippocrates, the father of Western Medicine himself, was a proponent and proclaimed: “Instead of using medicine, rather, fast a day.” Indeed, weight loss related to fasting lowers the risk of obesity-related diseases including diabetes and certain cancers, while fasting itself can be effective at reducing inflammation and risk of related diseases such as Alzheimer’s, cardiovascular disease and arthritis [2].
There are various types of fasting used in modern day primarily for weight loss, the most popular being intermittent, restricting food regularly for a set number of hours, and periodic or prolonged fasting, which last for longer than two days. A new version of fasting is the ProLon fasting mimicking diet, a five-day prolonged fast that allows users to continue to eat with a plant-based, calorie-restricted meal programme designed to nourish the body while still receiving the cell-rejuvenating benefits of a conventional fast. ProLon combines macronutrients and micronutrients without triggering the nutrient sensing pathways, therefore maintaining the fasting state and promoting weight loss, healthy eating and cell rejuvenation. Studies have proven the benefits of fasting and the ProLon diet to health and longevity [3]. Whichever method you follow, there are ways to optimise your fast to make it safer, easier and more enjoyable.

Staying hydrated: what can you drink during a fast

Although fasting is based on the principle of limiting caloric intake, drinking certain fluids is not only allowed but encouraged. Aim to drink around 32fl oz (1 litre) of water per day in addition to any other drinks or fluids within your fasting program. You can also drink carbonated water, and either a small cup of black coffee or two cups of black or green tea if you are craving caffeine. However, caffeine mildly activates nutrition-sensitive pathways, so limit your intake to one or two cups only. If you begin to feel thirsty or lightheaded, listen to your body’s signals and drink more. Fasts like the ProLon fasting mimicking diet allow users to consume a restricted amount of food, reducing the risks of such side-effects.

Keep moving: exercising while fasting

While strenuous exercise is not recommended during caloric restriction, mild aerobic exercise for a maximum of one hour is encouraged to benefit your health and distract your mind from any food cravings. Good examples include walking or yoga. Exercise can actually enhance your fast as it places the body under a similar stress to that of caloric restriction and helps your body burn a specific type of fat reserve intramyocellular lipids (IMCLs). Once this energy source is depleted, stored fat from other parts of the body are used to replace the oxidised IMCLs (usually the hard-to-lose fat located around the tummy, hips, thighs). Since fasting metabolises fat reserves rather than protein found in muscle, weight training will not prevent muscle growth [4].

Overnight fasting

A simple way to fast is to incorporate it into your sleep schedule by eating according to the body’s natural circadian rhythm which monitors the metabolism. For example, restricting food during the morning and evening can achieve a 12-13 hour fast overnight, providing your body with nutrients during the day and rest overnight. In fact, some of us fast every night without even realising it. A longer overnight fast of 14-16 hours can provide additional autophagy benefits. Normally, adults require between 7-9 hours of sleep to allow the body to recover from the day’s activities. During caloric restriction, the body may need even more than this so heading to bed early for some long, quality sleep is recommended. Indeed, lack of sleep is associated with an increase in the hunger hormone ghrelin and a decrease in the hormone leptin that indicates fullness, making it harder for you to fast successfully [5].

Fasting with meditation

Fasting has been used throughout history and across religions to achieve mental clarity and focus. Mindful practices like meditation can aid with your fast by keeping you calm, centred and focused on the way to achieving your fasting goals.

Staying motivated during caloric restriction

Going against your body’s natural instinct to eat can feel uncomfortable, therefore staying motivated during your fast is imperative especially during prolonged fasts. Surrounding yourself with positive affirmations through journaling, leaving encouraging notes around your living space, or verbalising your goals to yourself can all help.

How to avoid side-effects

While caloric restriction is generally safe and most users do not experience any negative side-effects, the most common mild side effects include headache and fatigue. To combat this, try to avoid strenuous exercise and environments like hot tubs or saunas. Increase your water intake and add salt to balance electrolytes if you begin to feel faint and over the counter pain medications to alleviate headaches. Another seemingly unavoidable side effect of caloric restriction is hunger pangs that can be difficult to ignore and require strategies to deal with them. L-Nutra’s Fasting.com recommends pre-planning your food shopping list, cooking schedule for meal prep, and free time with friends and family so that you are ready to eat as soon as feasting hours begin and to prevent your daily life from interrupting your fast. When you finally do eat, try to include foods high in fibre and carbohydrates like fruit, vegetables and wholegrain bread and pasta. This will both provide your body with nutrients and help you feel fuller for longer [4].