Intermittent Fasting: Lose Weight Without Starving?

Losing weight without starving and being energetic and efficient at the same time – that’s what many people who want to lose weight hope for from intermittent fasting. The fan base of the so-called intermittent fasting is growing. Unlike traditional  fasting  , you don’t go without eating for days or even weeks. The fasting phases are manageable and alternate with phases of normal nutrition – this rhythm can be integrated very well into everyday life. In addition to weight loss, periodic fasting should also improve sugar and fat metabolism. How intermittent fasting works, what it brings and how healthy this form of dieting is, you will learn below.

What is intermittent fasting?

Intermittent fasting, also   known as intermittent fasting , is characterized by the alternation of phases of eating and phases in which nothing is eaten – i.e. you fast at intervals.

There are different forms of intermittent fasting: it can be fasted by the hour, but also for a whole day. Intermittent fasting does not require any complicated instructions or a special diet plan – the intervals between eating and fasting are decisive.

Intermittent fasting according to plan: what methods are there?

Depending on how long the intervals last, there are different methods of intermittent fasting. The most well-known forms are:

• the 16:8 method
• the 5:2 method
• the 1:1 method
• the 12:12 method

In addition, different spellings are common, for example “16/8 method”, “16-8 method” or “5 to 2 method”. All designations describe the ratio of the duration of eating to fasting intervals.

What does 16:8 intermittent fasting mean?

16:8 intermittent fasting is the most popular form of intermittent fasting. Here the time in which you can eat is limited to eight hours. The remaining 16 hours of the day are fasted – in this context one also speaks of the  8-hour diet.

A  daily schedule  with this method could therefore be such that you only eat between 11 a.m. and 7 p.m. every day. Only calorie-free drinks are allowed until 11 a.m. the following morning. Alternatively, you can set the eating phase from 8 a.m. to 4 p.m. and skip dinner.

One of the special advantages of intermittent fasting: Such a plan can be  flexibly adapted.  If, for example, a social dinner is imminent, the fasting phase can be extended so that the 8-hour time window for eating is pushed back in time.

Intermittent fasting in a 5:2 ratio

With the 5:2 variant, you eat normally five days a week, i.e. without meal breaks and restrictions. On the two remaining days, calorie intake is limited to around 500 kcal (kilocalories) for women and 600 kcal for men.

Ideally, on these days you should avoid easily digestible  carbohydrates , such as those found in pasta,  wheat flour  or sugar, and instead use low-sugar fruit,  vegetables  and lean protein sources.

Ideally, choose non-consecutive days for the two days of fasting, on which you also have little  stress  .

1:1 method and 12:12 method – fasting and eating in unison

“Eat Stop Eat” or alternate fasting describes the  1:1 method of intermittent fasting. In this form, one day is alternately abstained from and the next day eaten normally.

With the  12:12 method,  the intervals are only 12 hours each – a relatively short form of “part-time fasting”. For example, you can set the time window for eating between 7 a.m. and 7 p.m. – a normal daily schedule for many anyway. Due to the comparatively short meal break, however, this is not a common variant of intermittent fasting.

Intermittent fasting for beginners

The 16:8 form of intermittent fasting is particularly suitable for beginners, since the night’s rest is part of the meal break. If you like: losing weight while you sleep, which often also contributes to an improvement in the quality of your sleep.

By the way: The 16:8 interval fasting has been promoted in particular by the television doctor Dr. Eckart von Hirschhausen became very well known, who was able to achieve considerable success with it and lose ten kilograms – this form of fasting is therefore sometimes also referred to as the  Hirschhausen diet  .

What can you eat during intermittent fasting?

Intermittent fasting is based on a healthy diet, but without making specific specifications or imposing restrictions. So you should neither overeat nor meticulously count calories during the eating phases. As is so often the case with intermittent fasting, a healthy and balanced mix is ​​the key to success.

During the  fasting phases  you should only drink, and if possible calorie-free – the best are:

• Water (optional with a dash of  apple cider vinegar  or a slice  of lemon )
• thin vegetable broth
• heavily diluted juice spritzers
• unsweetened  tea

Coffee  is also  allowed, but without sugar and sweeteners. Those who drink their coffee with  milk  can continue to do so. Milk does have some calories, but a small sip won’t negate the success of intermittent fasting.

In longer periods of fasting, a homemade vegetable or  chicken broth can  help to supply the body with nutrients and alleviate the feeling of hunger.

Is alcohol allowed with intermittent fasting?

Just as you can eat normally during the eating phases, alcohol is also allowed during intermittent fasting. But of course only in moderation.

However, alcohol is taboo during periods of fasting.

Lose weight with intermittent fasting?

Scientific studies in mice ¹  have shown that intermittent fasting can improve weight problems. It is not necessary to reduce the amount of calories in order to achieve weight loss.

A pilot study with human subjects also seems to prove this. ^Another  study also showed that intermittent fasting lost less fat-free mass than a calorie-restricted diet. ³

How does intermittent fasting work?

In contrast to other  diets, the principle of action of intermittent fasting  is not based on the reduction of calories, but aims to induce the body to adapt its metabolism by taking long breaks from eating.

The theory behind it: If a meal break lasts more than 14 hours, the body switches from burning carbohydrates to  burning fat  – and uses the fats stored in the body to do so.

In contrast to a crash diet, in which the  metabolism  switches to “economy mode”, intermittent fasting should not  have a yo-yo effect  . For this reason, intermittent fasting is often used to lose weight.

Other health effects

But other health-promoting aspects could also be observed in the mouse study mentioned above. The blood values  ​​of the  mice were   improved and the risk of  cardiovascular diseases  was reduced. An anti-inflammatory effect and an improvement in LDL cholesterol levels have also been shown several times.

If food intake is distributed throughout the day, the body repeatedly releases  insulin  . However, the insulin prevents fat burning for several hours. Over time, the body cells develop an immunity to insulin and thus a precursor to  diabetes .  Such a disorder can possibly be counteracted by intermittent fasting. This is indicated by studies in which an improvement in insulin sensitivity could already be determined. ⁴

Another positive consequence of intermittent fasting is an increased release of the growth hormone  somatropin. This hormone affects fat metabolism and protein synthesis. This results in increased muscle growth.

Cell cleansing through intermittent fasting

The effect of cell recycling – the so-called  autophagy  – is also often mentioned in connection with intermittent fasting. In the fasting phase, the individual cell gains its energy from components that are not essential for survival, for example from old and defective cell parts – in this way the cell cleans itself.

However, overeating disrupts this process. By fasting, on the other hand, the body is no longer busy with digestion and can turn to cell cleansing. Animal studies even indicate that this effect could have a life-prolonging effect. ^5.6

7 tips: This is how intermittent fasting works

For a successful intermittent fasting you should heed the following tips:

1. Start slowly: To get started, it may be advisable to start with a 12-hour fasting interval and then slowly increase the fasting period to 16 hours.
2. Do not expect too much: Avoid physical exertion during the fasting intervals, especially at the beginning.
3. Eat a balanced and healthy diet with plenty of vegetables and  protein  and not too many carbohydrates.
4. Avoid snacking between meals, as well as excessive gluttony – just eat normal portions.
5. Be sure to drink plenty of fluids throughout the day. It is best to start the day with a glass of water in the morning.
6. Some exercise on an empty stomach can help boost digestion. Walking or jumping rope for 10 minutes can be enough.
7. Coffee or other  flavored beverages , such as a glass of water with a slice of lemon, can help stave off hunger pangs.

How long should intermittent fasting last?

How much and how quickly you can lose weight with intermittent fasting varies greatly and of course also depends on how you eat during the eating phases. There is no time limit for the fasting method. If the focus is on losing weight, you can slowly reduce intermittent fasting and gradually end it when you have reached your weight goal.

However, it is also possible to use intermittent fasting as a long-term diet. It is sufficient, for example, to fast three days a week according to the 16:8 method.

Side effects and disadvantages of intermittent fasting

Dizziness,  headaches  and freezing can occur as side effects, especially at the beginning of intermittent fasting. However, these minor side effects usually subside after an initial period of adjustment.

A possible cause of dizziness that occurs can be a lack of salt. Adding a pinch of  salt  to a glass of water can help. You should also make sure you drink enough. Hot tea, a warm footbath and an extra layer of clothing help against freezing.

Who is intermittent fasting not suitable for?

In principle, every healthy person can try intermittent fasting. However, like other diets, intermittent fasting is considered unsuitable for children, adolescents, breastfeeding women and pregnant women because the risk of  nutrient deficiency  is too great. The same applies to older people and people who are severely  underweight  or have eating disorders.

If you are taking  medication  , you should discuss with your doctor before you start fasting whether intermittent fasting is suitable for you. Caution is particularly important for people with diabetes, as fasting can lower blood sugar levels, which can be dangerous in combination with blood sugar-lowering medication.

In the case of  previous illnesses  such as  cancer , metabolic diseases,  low blood pressure  or chronic diseases, it is also advisable to speak to a doctor first.

Criticism of Interval Fasting

Even if the first scientific studies attribute positive effects to intermittent fasting, there is also criticism. The DGE (German Society for Nutrition)  does not attribute any lasting benefit to intermittent fasting  : “The DGE does not consider this method to be useful for regulating weight in the long term. This does not result in a switch to a health-promoting diet.” ⁷

Researchers from the German Cancer Research Center in Heidelberg also certify that the 5:2 method is no better at losing weight than reducing the daily calorie intake. ^8th

The number of human medical studies on the effectiveness of intermittent fasting and its effects on health is still low, and  there are no long-term studies  . The results often contradict each other or the scientists draw different conclusions from their observations. In addition, the various studies work with different types of intermittent fasting, which means that the results are hardly comparable. It is therefore still too early to make a final assessment of the benefits or possible side effects of intermittent fasting. ⁹

Conclusion: Intermittent fasting can be worthwhile

The effects observed in studies indicate that not only the what, but also the when can be decisive for a healthy and vital body. Even if the effect of the fasting method has not yet been sufficiently investigated, many scientists see the potential in intermittent fasting to counteract diseases – negative effects cannot be derived from previous studies.

However, every part-time fasting person must be aware that not everything should be eaten during the eating phases, and certainly not in excessive amounts.  It is important to keep an eye on the amount eaten and the nutritional content of the  food , so making healthy food choices is highly recommended. It is not in the spirit of intermittent fasting to eat more than is actually necessary in order to be able to survive the following meal break better.

With a balanced diet, intermittent fasting could help to increase your own well-being and also lose annoying pounds. Intermittent fasting is not just a diet, it is a way of eating to maintain weight and feel good about it. In combination with healthy recipes and exercise to balance everyday life, intermittent fasting can be a good basis for long-term (weight loss) success.