In nature, because food is not always available, intermittent fasting is part of the survival routine and any animal organism can handle it.
For humans, fasting means refraining from consuming some or all foods , beverages or both, for a period of time that can be determined or indefinite.
Absolute fasting is defined as the failure to eat any solid or liquid food for a certain period, usually between 24 hours and a few days.
Imposed Fast
For evolutionary reasons, the human body (thanks to its hormonal flows) is able to adapt optimally to the absence of food. The same cannot be said for overeating , as a result of which you can get sick of the so-called diseases of well -being ( obesity , dyslipidemia , type 2 diabetes mellitus , hypertension , etc.).
In this regard, some specialists propose to treat overweight and metabolic diseases through the so-called therapeutic fast. This practice takes place under conditions of medical supervision and nutritional support (withfood supplements and water ).
Beneficial or Harmful?
Fasting can be beneficial or harmful based on some factors; for example: duration, completeness of food abstention or nutritional support, medical control, pathological conditions for its application, etc. Not all forms of fasting are the same; some are extremely debilitating and unmotivated, others less exhausting and more rational.
Fasting, whether controlled or uncontrolled, therapeutic or not, is still very stressful for the body and mind. However, its potential harmfulness mainly depends on the parameters with which it is programmed.
An example of ethically “highly questionable” fasting is the so-called tube diet. This is based on a form of chronic fasting, during which the organism is supported exclusively by enteral artificial nutrition ( nasogastric tube ). Similar practices can induce:
- Physical debility and tendency to malnutritionand ketosis (see below)
- Limitation of motor activities
- Food miseducation.
On the contrary, in subjects suffering from metabolic pathologies, short periods of food interruption – such as, for example, the emphasis on the night fasting period (the one during sleep , taking it from 8 to 12 or 14 hours) – does not cause side effects. and favor the remission of certain metabolic parameters (especially hyperglycemia and hypetriglyceridemia) or other disorders ( fatty liver , gastroesophageal reflux , etc.). Obviously, the example just reported does not represent a real fast and this is the only form of food abstention potentially beneficial and free of side effects.
Many believe that absolute fasting can negatively affect hormonal flows, specifically by suppressing the action of the thyroid gland (the one that secretes the hormones responsible for regulating metabolism); this is only partially true. In fact, prolonged fasting undoubtedly reduces the secretion of thyroid hormones , however, in general, this reduction does not occur before 24 or 48 hours.
There is some scientific evidence showing that fasting can play an important role in people receiving chemotherapy , but more studies are needed to define its real efficacy and possible clinical application.
Can It Be Therapeutic?
Some centers specialized in the treatment of metabolic pathologies use therapeutic fasting for weight reduction and for the restoration of metabolic parameters.
Therapeutic fasting systems rarely rely on irrevocable abstinence from food, and none of these prohibit the use of water. On the contrary, the tendency is to encourage the intake of liquids and, sometimes, of certain plant foods in certain portions (especially in the case of certain particular diseases).
According to the experience of the operators who propose therapeutic fasting, the greatest difficulty consists in the initial acceptance of the therapy, not in the protocol itself. Few believe they can survive 2 or 3 weeks without eating but, on the other hand, many have spontaneously reached 30-40 days.
How does it work?
The first 24-48 hours of therapy include complete fasting with the sole intake of water.
In this phase (the hardest), the body consumes most of the sugar and triglycerides present in the blood ; obviously, glucose levels are kept progressively stable by hepatic glycogen , while motor action (typified by absolute rest) is mainly supported by muscle glycogen stores .
ATTENTION! As of now, it is already clear enough that this technique cannot be used in the case of liver impairment, type 1 diabetes mellitus or other diseases that involve significant metabolic difficulty.
The “true” metabolic action (or rather, the one sought by therapists) occurs at the end of this first phase, that is when the glycogen reserves are reduced “to the bone”. At this point, the body begins to burn mainly the adipose tissue , with the production and blood flow of molecules called ketones .
Sometimes, in compromised subjects or those who take certain drugs, therapeutic fasting involves the intake of vegetable juices such as squeezed and centrifuged to reduce the state of ketoacidosis.
Therapeutic fasting is interrupted in progressive matters, starting with the intake of juices and centrifuged, then of smoothiesand vegetables in pieces, reaching up to the intake of cereals and legumes .
Effects
Fasting and Acidosis
Although ketones are potentially toxic (if not effectively disposed of by the body), they can have positive effects on therapeutic compliance (tolerance of the strategy).
In fact, by acting in a suppressive manner towards the central nervous system , ketones reduce the stimulus of hunger to a minimum .
Some even claim that ketones can cause a feeling of general well-being. However, this condition called “ketoacidosis” is not free from side effects, including: liver and kidney toxicity, tendency to dehydration , hypotension , etc.
Fasting and Digestive Rest
Those who propose therapeutic fasting affirm that this feeling of well-being is not attributable only to ketoacidosis, but also to the total rest of the gastrointestinal tract.
Indeed, the digestion of subjects suffering from obesity is always a rather demanding process; consuming very abundant meals, not very digestible and responsible for high glycemic peaks , these people are used to living with a feeling of almost continuous psycho-physical weakness.
Fasting and Cell Washing
A further beneficial effect of therapeutic fasting, further emphasized by the administration of antioxidant supplements , is the “cell washing”. Not everyone knows that the organism has various means of excretion of useless or toxic molecules; these include bile , faeces , urine , sweat , mucus , lung ventilation , hair , hair , nails , etc.
Therapeutic fasting makes it possible to exploit these mechanisms without simultaneously taking in other pollutants or other toxic agents, among which we remember: mercury , arsenic , lead , dioxin and food additives .
Fasting and taste buds
Another great advantage of therapeutic fasting is the restoration of the gustatory papillary function of the tongue, which occurs through a process called neuroadaptation.
This perceptual “reset” effect of tastes is very useful for the subsequent reorganization of the diet (maintenance phase), which involves the exclusive use of fresh and lightly seasoned foods .
Recommendations
Therapeutic fasting violates any principle of dietetics and nutritional balance. It is a radical intervention that could find application in the replacement of bariatric surgery (to be adopted on the very obese).
It must be remembered that ketogenic diets have a very deleterious effect on the body, starting from kidney fatigue up to the wasting of muscle tissue . For more information, see the article: Ketogenic Diet ? No thank you!
Regardless of personal and / or professional opinion, it is important to emphasize that it is objectively a technique that can ONLY be practiced within specialized structures, where medical personnel are able to supervise the entire process and, if necessary, administer drugs. or specific supplements. Supervision and monitoring mainly observe: blood pressure , blood volume , blood sugar , metabolic acidosis , etc.
The nutritional supplements, on the other hand, are vitamin, saline and amino acid in nature; the overall advice for those facing therapeutic fasting is to suspend any drug treatment, except for those irreplaceable (eg thyroid hormones, drugs for pressure in case of congenital defects, etc.).
In the presence of certain pathologies (organic or psychiatric), of special physiological conditions ( pregnancy , breastfeeding ), old age and growth , therapeutic fasting is totally not recommended
