The Liver Cleansing Diet: Love your liver and live longer is a book by Sandra Cabot that has sparked much recent interest in liver cleansing diets. Liver cleansing diets claim to remove toxins that are clogging the liver. This cleansing of the liver is proposed to help it to work more efficiently, leading to weight loss. A range of nutritional supplements and liver tonics are often recommended to accompany liver cleansing diets. Despite the popularity of these diets (Cabot’s book has sold over 1.4 million copies) there is little scientific evidence to support the claims made by their proponents.
The liver is an important organ in the human digestive system and is situated in the upper, right-hand part of the abdomen. It is the largest gland in the human body and weighs about 2kg in an adult human. The liver is served by two main blood vessels: the hepatic artery which carries oxygenated blood from the heart to the liver, and the hepatic portal vein which carries nutrient-filled blood from the stomach and the intestines, to the liver. The liver holds approximately 13% of the body’s total blood supply. It has several key functions that include:
Removal of damaged red blood cells and toxins (such as alcohol and nicotine) from the blood.Conversion of glucose (sugars from food) to glycogen for storage.Conversion of glycogen back to glucose to provide energy for the body.Conversion of excess proteins and amino acids into urea for excretion by the kidneys.Production and storage of vitamins and minerals (such as copper and iron). Production of bile (chemicals which help to break down fats in the intestine).Production blood clotting factors.Liver cleansing diets can be classified under the umbrella of ‘detox’ or detoxification diets. They claim that the body (in particular the liver) needs cleansing in order to help it function better. Liver cleansing diets often focus on eliminating toxins that enter our bodies through the food that we eat. They also claim to aid in weight loss.
The diet
The dietary recommendations of liver cleansing diets are generally in line with a healthy eating plan. The diets usually suggest avoiding sugar, caffeine, alcohol, and fatty foods, while increasing intake of grains, water, fresh fruits and vegetables. In particular they focus on eating unprocessed foods. Processed foods (foods that are no longer in their natural state) can include more additives (such as salt and sugar) and preservatives (natural or synthetic chemicals added to foods to prevent spoiling). Liver cleansing diets tend to be time-limited, and therefore offer an attractive short-term option for people attempting weight loss.
The tonics and supplements
Liver cleansing diets often recommend supplements to aid in the cleansing process. There is a range of different supplements available. Most contain a mix of herbal or plant-based ingredients.
How does the diet help with weight loss?
According to proponents of liver cleansing diets, a change in diet can lead to a more efficient functioning liver. It is the improved liver functioning that is proposed to lead to weight loss. Current medical and scientific opinion about how the liver operates does not suggest that the liver has a primary role in weight control. However, nutritionists have noted that the diet itself, regardless of its purported effects on the liver, should lead to weight loss in the short-term. Liver cleansing diets tend to recommend low calorie foods. Consuming less energy than the body requires is a scientifically well-evidenced and accepted method for weight loss.
What is the evidence that liver cleansing diets work?
Most ‘evidence’ in support of liver cleansing diets is anecdotal. That is, proponents of the diets will outline success stories from individual patients or clients. As outlined above, the liver cleansing diet may lead to weight loss due to the consumption of a healthy and balanced diet. However, there is little evidence to suggest that the liver can be cleansed by eating certain foods, or by taking supplements or tonics.
Scientists rely on stringent criteria to judge whether a particular supplement or diet leads to its claimed benefits. One way to show that a supplement works, in the way it is supposed to, would be to conduct a clinical trial. Clinical trials could allow scientists to carefully observe what happens to the livers of patient when they consume these supplements. However, to date, there have been no clinical trials or any other peer-reviewed studies that show how the diet or supplements affect liver functioning. The recommended supplements are expensive, and, at best, unnecessary (especially if you are eating a balanced diet). Supplements are often untested and can be harmful if patients are allergic to the ingredients, or if the supplements interact with prescription medications.
There is no scientific evidence to suggest that it is necessary, or even possible to ‘cleanse’ the liver. The body naturally removes toxins through the liver, kidneys, and intestines. People who lead healthy, active lifestyles do not need to take extra steps to remove the toxins from their livers or bodies. However, if an individual’s diet or lifestyle includes high fat foods, high sugar foods, caffeine, alcohol, cigarettes, drugs, or limited exercise, then a change in diet or lifestyle to prevent toxins entering the body is the healthiest and most effective approach to detoxification.
Liver cleansing diets recommend foods and lifestyle choices that will tend to result in less toxins entering the body.These diets may lead to weight loss and other health benefits (such as improved skin quality and reduced fatigue) due to better lifestyle choices, for example eating healthy foods, and eating less fatty and sugary foods (rather than because of any effects on the liver).The diet recommendations are sensible and nutritious if adopted over the long-term. The theory behind liver cleansing diets is not supported by scientific research.There is little scientific evidence to support the use of the supplements and tonics recommended to accompany these diets.Some supplements can interact with prescription drugs and should not be taken without appropriate medical advice.Liver cleansing diets tend to focus exclusively on liver functioning as the solution to weight loss, to the neglect of other weight loss methods (i.e. physical activity). A regular diet that contains whole grains and unprocessed foods is good for your body.Don't take any supplements without discussing them with your doctor.Sustained exercise, a balanced diet and a healthy lifestyle are the best ways to remove toxins from the body.
