Detox diets, often marketed as quick fixes to cleanse the body and promote rapid weight loss, have gained popularity in recent years. From juice fasts to lemon cleanses and liver detox regimens, these approaches promise improved digestion, reduced inflammation and a sense of renewal.
But health experts caution that while such diets may offer short-term benefits, they also carry significant risks, including nutrient deficiencies, fatigue and long-term metabolic effects.
What are detox diets?
Detox diets are dietary regimens designed to help the body “cleanse” itself of toxins, usually by restricting certain foods and prioritizing others believed to aid the cleansing process.
There are many approaches to detox diets. Some last only a few days, while others extend for months. Some involve consuming only liquids, while others allow solid foods but eliminate certain categories. Others are based on fasting or enemas. The most common types include:
Juice fasting
This method involves drinking only fruit and vegetable juices for several days.
Advantages: This diet is rich in vitamins and minerals that are easily absorbed in liquid form. Juicing removes fiber, which can sometimes inhibit absorption, while giving the digestive system a break. Juice diets may reduce bloating, improve bowel movements in the short term, and contribute to rapid weight loss.
Disadvantages: Juice diets can cause nutritional deficiencies. They are typically low in protein, essential fats, and certain vitamins and minerals, leading to muscle loss, fatigue, or anemia. The most concerning deficiencies include vitamin B12, vitamin B1, iron, calcium and zinc.
Juice diets are often high in simple sugars, which can trigger blood sugar spikes and, over time, insulin resistance. Extended low-calorie juice diets may also slow metabolism. Prolonged consumption of green juices can raise oxalate levels, which bind to calcium and may cause kidney stones, while simultaneously reducing sodium levels through excessive urination — a combination that can create dangerous electrolyte imbalances, leading to fatigue, weakness, dizziness and even heart rhythm disturbances.
While juices can be part of a healthy, balanced diet, juice-only regimens lasting more than a few days may cause serious harm. Professional consultation is advised before starting.
Lemon diet (Master Cleanse)
This extreme liquid diet involves consuming a mixture of water, lemon juice, maple syrup and cayenne pepper for several days or weeks.
Advantages: The primary benefit is rapid weight loss due to the very low calorie intake. The diet eliminates processed foods and refined sugar, which may help the body “reset” from high-calorie, processed eating habits. Reduced calorie and sugar intake can also improve insulin sensitivity, similar to findings from intermittent fasting studies. The high lemon content may provide immune-boosting vitamin C.
Disadvantages: This is a highly restrictive diet, and medical literature reports that it can lead to protein deficiencies, causing muscle loss and weakened immunity. A lack of essential fats may impair brain function and hinder absorption of fat-soluble vitamins. Despite calorie restriction, the maple syrup provides high amounts of simple sugars, which may trigger glucose spikes and long-term insulin resistance.
The diet can also irritate the digestive system: cayenne pepper may inflame the stomach lining and cause diarrhea, while lemon juice may worsen acid reflux or stomach irritation in sensitive individuals. Electrolyte imbalances are another risk, as frequent diarrhea and inadequate intake of sodium and potassium can cause heart rhythm disturbances and general weakness.
While one or two days on the lemon diet is unlikely to cause harm, it is medically discouraged as a long-term regimen due to significant health risks.
Liver detox diet
A liver detox diet is based on consuming foods believed to support detoxification processes, such as leafy greens, beets, garlic, roots (like ginger and turmeric) and plenty of fluids. The aim is to improve liver function by increasing foods thought to benefit it while reducing processed foods, saturated fats and alcohol. However, it should be noted that not all foods commonly believed to support the liver have proven scientific evidence of their effectiveness.
Advantages: This diet emphasizes large amounts of leafy greens, particularly cabbage and spinach, which are rich in antioxidants. It also includes beets, which contain betalains shown in some studies to support liver detoxification, and garlic, which contains allicin and sulfur compounds that may stimulate enzymes involved in neutralizing toxins. With its high vegetable content, this diet may help reduce inflammation, improve liver enzyme levels, aid digestion and balance gut bacteria. A wide variety of vegetables also contributes to improved cholesterol and blood sugar regulation, and supports weight loss.
Disadvantages: Like other detox regimens, this diet can also result in nutritional deficiencies, fatigue, dizziness and loss of muscle mass.
In general, detox diets are said to offer several benefits: Rapid, though often temporary, weight loss; improved digestive function, with lighter meals reducing bloating and improving bowel movements; reduced inflammation, as greater intake of fruits and vegetables and avoidance of processed foods may ease chronic inflammation; higher intake of vitamins and antioxidants through plant-based foods; a psychological “reset” effect, with a feeling of cleansing and renewal that may help refocus eating habits. Cutting out addictive foods such as caffeine, alcohol and sugar can also produce a temporary sense of relief.
But research also points to significant risks when such diets are prolonged: Nutritional deficiencies, as fasting or cutting out entire food groups can cause shortages of protein, iron and key vitamins; fatigue, headaches and dizziness; muscle loss from insufficient protein intake, especially in extended fasts; metabolic changes, as the body slows its rate of energy expenditure, making long-term weight management harder; negative psychological effects, with food restriction often leading to overeating afterward. Studies also show such diets raise levels of ghrelin, the hunger hormone, increasing appetite after the cleanse phase.
Bottom line: The appeal of cleansing the body of toxins and losing weight quickly is understandable. But despite the perceived benefits, particularly if followed for long periods, the drawbacks often outweigh the advantages. Detox diets are not essential for healthy function — organs such as the liver and kidneys naturally cleanse the body. Just as there are no shortcuts to cleaning your home, there are no shortcuts to “detoxing” the body. Sustainable healthy eating habits are more effective than extreme diets.
- The author is a clinical dietitian with Clalit Health Services.