Diet Myth or Truth: Fasting Is Effective for Weight Loss

Typical Fasting Weight Loss Plans

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But the risks far outweigh any benefits, and ultimately, fasting can cause more harm than good. But high-risk people, the elderly, anyone with a chronic disease, pregnant women, and children are advised against any type of fasting. Liquid diets Very low calorie. National Heart, Lung, and Blood Institute. Two experimental diets were selected for the DASH study and compared with each other, and with a third: The Truth About Fasting The bottom line:

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Some can be perfectly safe, such as medical fasts supervised by a physician. Religious and cultural fasts are typically undertaken as an act of devotion, last from hours, and are not intended to promote weight loss. Fasts lasting a day or two are unlikely to be dangerous for most healthy adults.

But high-risk people, the elderly, anyone with a chronic disease, pregnant women, and children are advised against any type of fasting. The real danger lies in staying on the fast for prolonged periods, anywhere from three days to a month. When you dramatically reduce your calorie intake, you will lose weight.

But it can also cause all kinds of health problems, including muscle loss. Further, when you start fasting, your body goes into conservation mode, burning calories more slowly. Keep in mind that the initial weight lost on a fast is primarily fluid or "water weight," not fat. And when you go back to eating, any lost weight usually gets a return ticket back.

Not only do most people regain weight lost on a fast, they tend to add a few extra pounds because a slower metabolism makes it easier to gain weight. Worse, the weight that is regained is likely to be all fat -- lost muscle has to be added back at the gym. Side effects of fasting include dizziness , headaches , low blood sugar , muscle aches, weakness , and fatigue. Prolonged fasting can lead to anemia , a weakened immune system, liver and kidney problems, and irregular heartbeat.

Fasting can also result in vitamin and mineral deficiencies, muscle breakdown, and diarrhea. When you drink laxative concoctions during a fast, there is an increased risk of fluid imbalance and dehydration. The risks get more complicated and severe the longer you stay on a fast, or if you repeatedly go on fasts.

The higher the BP, the greater is the chance of heart attack, heart failure, stroke, and kidney disease. The prevalence of hypertension led the U. National Institutes of Health NIH to propose funding to further research the role of dietary patterns on blood pressure. In the NHLBI worked with five of the most well-respected medical research centers in different cities across the U. The DASH study used a rigorous design called a randomized controlled trial RCT , and it involved teams of physicians, nurses, nutritionists, statisticians, and research coordinators working in a cooperative venture in which participants were selected and studied in each of these five research facilities.

The chosen facilities and locales for this multi-center study were: Two DASH trials were designed and carried out as multi-center, randomized, outpatient feeding studies with the purpose of testing the effects of dietary patterns on blood pressure. The standardized multi-center protocol is an approach used in many large-scale multi-center studies funded by the NHLBI.

A unique feature of the DASH diet was that the foods and menu were chosen based on conventionally consumed food items so it could be more easily adopted by the general public if results were positive.

The nutritional conceptualization of the DASH meal plans was based in part on this research. Two experimental diets were selected for the DASH study and compared with each other, and with a third: Magnesium and Potassium levels were close to the 75th percentile of U. The DASH diet was designed to provide liberal amounts of key nutrients thought to play a part in lowering blood pressure, based on past epidemiologic studies. One of the unique features of the DASH study was that dietary patterns rather than single nutrients were being tested.

Researchers have also found that the DASH diet is more effective than a low oxalate diet in the prevention and treatment of kidney stones, specifically calcium oxalate kidney stones the most common type. Participants ate one of the three aforementioned dietary patterns in 3 separate phases of the trial, including 1 Screening, 2 , Run-in and 3 Intervention. In the screening phase, participants were screened for eligibility based on the combined results of blood pressure readings.

In the 3 week run-in phase, each subject was given the control diet for 3 weeks, had their blood pressure measurements taken on each of five separate days, gave one hour urine sample and completed a questionnaire on symptoms. At this point, subjects who were compliant with the feeding program during the screening phase were each randomly assigned to one of the three diets outlined above, to begin at the start of the 4th week.

The intervention phase followed next; this was an 8-week period in which the subjects were provided the diet to which they had been randomly assigned. The first group of study subjects began the run-in phase of the trial in September while the fifth and final group began in January Alcohol was limited to no more than two beverages per day, and caffeine intake was limited to no more than three caffeinated beverages.

The minority portion of the study sample and the hypertensive portion both showed the largest reductions in blood pressure from the combination diet against the control diet. The hypertensive subjects experienced a drop of At the end of the intervention phase, Apart from only one subject on the control diet who was suffering from cholecystitis, other gastrointestinal symptoms had a low rate of incidence.

Like the previous study, it was based on a large sample participants and was a multi-center, randomized, outpatient feeding study where the subjects were given all their food. The day intervention phase followed, in which subjects ate their assigned diets at each of the aforementioned sodium levels high, intermediate and low in random order, in a crossover design. The primary outcome of the DASH-Sodium study was systolic blood pressure at the end of the day dietary intervention periods. The secondary outcome was diastolic blood pressure.

Study results indicate that the quantity of dietary sodium in the control diet was twice as powerful in its effect on blood pressure as it was in the DASH diet. As stated by Sacks, F. The DASH diet and the control diet at the lower salt levels were both successful in lowering blood pressure, but the largest reductions in blood pressure were obtained by eating a combination of these two i.

The hypertensive subjects experienced an average reduction of

Dangers of Fasting for Weight Loss