March 2019
Bartosz Malinowski, Klaudia Zalewska, Anna Węsierska, Maya M. Sokołowska, Maciej Socha, Grzegorz Liczner, Katarzyna Pawlak-Osińska, and Michał Wiciński
Abstract
Intermittent fasting is a form of time restricted eating (typically 16 h fasting and 8 h eating), which has gained popularity in recent years and shows promise as a possible new paradigm in the approach to weight loss and the reduction of inflammation, and has many potential long term health benefits.
In this review, the authors will incorporate many aspects of fasting, mainly focusing on its effects on the cardiovascular system, involving atherosclerosis progression, benefits for diabetes mellitus type 2, lowering of blood pressure, and exploring other cardiovascular risk factors (such as lipid profile and inflammation).
Summary
The IF diet limits many risk factors for the development of cardiovascular diseases and therefore the occurrence of these diseases. Fatty acids and ketones become the main energy fuel, because the body undergoes metabolic switching of glucose-ketone (G-to-K). By affecting the biochemical transformations of lipids, it decreases body mass and has a positive influence on lipid profile parameters—it reduces the concentration of total cholesterol, triglycerides, and LDL cholesterol.
Benefit from the use of the IF diet were confirmed in research on the development of atherosclerosis. Intermittent fasting inhibits the development of atherosclerotic plaque by reducing the concentration of inflammatory markers, such as IL-6, homocysteine, and CRP. The IF diet results in an increase in plasma concentrations of adiponectin and a decrease in leptin and resistin concentrations.
By altering the levels of these adipokines, it inhibits the adhesion of monocytes to vascular endothelial cells, neutrophils, and macrophage pro-active activity, and platelet aggregation. The transformation of macrophages into foam cells, the formation of extracellular deposits in vessels, and the proliferation and migration of endothelial cells into the inner arterial vascular membrane are limited.
The beneficial effect of the diet was observed in the prevention of hypertension. The intermittent fasting diet causes an increase of BDNF factor, which results in lowering the systolic and diastolic blood pressure by activating the parasympathetic system. BDNF causes acetylcholine to be released by the vagus nerve, which reduces the frequency of heart contractions.
The positive effect of the IF diet has also been documented in obese and diabetic people. The reduced amount of food consumed when using the IF diet results in a decrease in body weight. It also improves glucose metabolism and increases the sensitivity of tissues to insulin by increasing the B cells of the pancreatic islets. The IF diet also limits cardiac hypertrophy.
It remains questionable if these benefits are solely due to weight loss or non-weight loss mechanisms. The success of every type of diet depends on rule compliance—following a prescribed diet according to the circadian rhythm.
Despite the intermittent fasting diet having many benefits, its disadvantages are not without significance. Fasting may be dangerous and it is not recommended for people with hormonal imbalances, pregnant and breastfeeding women, and diabetics. Moreover, people with eating disorders, a BMI under 18.5, and underweight people are also not recommended to use the intermittent fasting diet.
In recent years, the IF diet and its varieties have become increasingly popular. This diet not only serves to reduce body weight, but can also be used as an effective non-pharmacological treatment method. This has been proven through various studies performed on people and animals. However, individuals’ current health and situation should be considered before commencing the IF diet.
