Detox diets have gained popularity as quick fixes to cleanse the body, especially after the consumption of excess food and drinks, common during the holidays. However, people should proceed with caution as these diets might have negative effects.

A few types of detox diets include fasting, juice cleanses, restricting self to certain foods, using detox supplements, or “cleansing” the colon with enemas or laxatives. These diets are generally short-term and claim to remove toxic substances from the body. The pattern these diets typically follow is a period of fasting and then an extremely restrictive diet for some days.

“As a registered dietitian, I have seen clients attempt detox diets and experience a slew of negative side effects, including developing a negative relationship with food,” Taylor Grasso, Dietitian at the University of Colorado Anschutz Medical Campus, said, as reported by Inverse.

“Research shows that there is little evidence to support the use of detox diets and that they are not needed anyway. The body is well-equipped to eliminate unwanted substances on its own, without expensive and potentially harmful supplements sold by the nutrition and wellness industry,” Grasso added.

On the contrary, these diets can lead to side effects, including headaches, fatigue, weakness, fainting, and irritability.

According to the Academy of Nutrition and Dietetics, there are foods that may boost the body’s detox system, including cruciferous vegetables like broccoli and Brussels sprouts, berries, artichokes, garlic, onions, leeks, and green tea. Moreover, adequate intake of lean protein may improve “the body’s natural system by maintaining adequate levels of glutathione, the body’s master detoxification enzyme, or catalyst.”

The few studies that have supported these detox diets have been found to be flawed, according to Grasso. The experiments are shown to have flawed methodologies and small sample sizes, and are often done on animals.

Additionally, supplements advertising detox benefits are not regulated by the U.S. Food and Drug Administration (FDA).

“In fact, some commercial supplements have raised so many health and safety issues that the FDA and the Federal Trade Commission have taken legal action against the companies that make them remove their products from the market,” Grasso noted.

Some detox rituals involving laxatives or enemas, or restriction of solid foods can lead to dehydration, nutrient deficiencies, and electrolyte imbalances, according to the outlet. Furthermore, diets that severely restrict certain foods can put the body into “starvation mode.”

“Doing that repeatedly over a long period can lead to a chronic decrease in metabolism, which means that the number of calories you burn at rest may slowly decrease over time. This can make it more difficult to lose weight and balance blood sugar. It can also leave people more susceptible to chronic metabolic conditions such as cardiovascular disease and diabetes,” the dietician explained.