Detox Diets

Myths vs. Reality

By Susan M. Kleiner, PhD, RD, FACN, CNS, FISSN

You are polluted, and we can clean you up! How appealing is that message?

Turn that message 180 degrees and think again: Your body is an amazing filtration machine, and here are some purification strategies to maximize your results!

The marketing angle of “your body is broken, and we know how to fix it” is, frankly, degrading. It is the tried-and-true strategy of “diet world” advertising, tearing down your spirit as well as your body. Advertisers position the product as “the great savior” for your ailing, dysfunctional body. This messaging is the antithesis of what appeals to the “sports and fitness world,” where we emphasize that your body is awesome, and we can help build it up stronger and faster. So it’s not surprising that one of the biggest diet marketing messages of the last decade has been that you are polluted, and we can clean you up. That message is virtually a myth with little supporting evidence. But the concept of a more pure diet to de-stress your body and maximize performance is certainly supported by scientific evidence in the real world.

Detox Diets - Myths vs. Reality

Facts Over Hype

An online keyword search for “detoxification” in the scientific literature database results in articles solely focused on drug, alcohol and heavy metal contamination, or the body’s natural metabolism of toxins and carcinogens. Searching again for the keywords “detoxification diet” results in articles about how certain foods (that we will discuss further) can support the body’s natural detoxification pathways, the effect of a gluten-free diet on celiac patients, research on how probiotics survive the body’s natural antibacterial defense systems, and research on mice, bees and caterpillars, among other animals and test tubes. There is not one study on any of the detox diets marketed to the public.

The fact that so many people claim that detox diets “work” is not all fantasy. The funny thing about any diet plan is that it restricts what the dieter eats and drinks. Detox diets eliminate almost everything that we know to be unhealthy, increase inflammation, and make us feel bad: alcohol, foods high in sugar, refined carbohydrates, saturated fats and trans fats, not to mention high intakes of caffeine, tobacco and other recreational drugs. For some short period of time, the dieter dramatically lowers calories, increases hydration, and takes tremendous control over their eating. The less health-promoting their diet and lifestyle was before the detox diet, the better they will feel from the cleanse. There isn’t one bit of evidence to tell us that the ingredients of the cleansing ritual did anything, but there is plenty of data to help us understand that good hydration, lots of plant foods, and eliminating processed, packaged and fast foods high in calories and low in nutrients will make you look and feel better.

Why not cleanse even if it just tricks us into doing the right thing for a few weeks? Research on successful weight loss is quite clear: It takes learning how to eat well and exercise daily to healthfully lose weight and maintain the weight loss. Detox diets don’t teach anything about how to eat well, and exercising during the cleansing ritual is discouraged. While there is data that people who have a good initial weight loss may have more motivation to stick with a program long term, quick weight loss without any information about changing food and exercise habits typically results in quick regain of the weight lost at least, and possibly greater fat gains.

Purification Optimization

Rather than an annual cleanse for one week, create a yearlong purification ritual for lifetime health and fitness. A fluid-filled, plant-based diet is the natural sustenance for your body’s amazing filtration systems and purification pathways.

The inside of your body meets the outside environment at the lining of your digestive tract. It is a high priority of the body to keep the intestinal membrane healthy to protect your body from environmental contaminants. The cells naturally turn over (die and are replaced) every 21 days. The scientific term is actually “exfoliation.” You can give your own intestines a “facial” of sorts by eating a high fiber diet. The fiber is not digested, and creates bulk as it works its way through the tract. As it pushes through it gently cleans up the lining, keeping it fresh and healthy. If you follow a purification diet that emphasizes lots of fruits and vegetables, grains and beans, nuts and seeds, you are by default increasing your fiber intake and cleaning up your intestines. At the same time the extra bulk helps things move through more quickly and efficiently, which usually helps to decrease intestinal discomfort and bloating, and lowers the risk of toxin absorption.

Beneficial bacteria and yeasts in our gut are partnered with many of the fibers from plant foods to protect us from environmental assaults and toxins. Beneficial cultures enhance immune function and promote optimal nutrition. Probiotic is the well-known term for the healthy cellular cultures that we consume in fermented foods like yogurt, kefir, sauerkraut, miso and tempeh. Eating these foods on a daily basis can help stimulate the immune system, promote healthy digestion and nutrition, and may reduce gas and bloating. Probiotics have their purifying effect by crowding out the unhealthy gut flora like yeasts, viruses and bacteria that trigger illnesses and disease. They can transfer some of their genetic disease-fighting capacity to our own intestinal cells. And they can alter the pH balance of our gut to reduce virulent organisms, and even enhance our own essential mineral absorption.1

Prebiotics, a newer concept, are the fibers that feed the probiotic cultures so that they can prosper. Prebiotics may also inhibit the ability of unhealthy colonies to attach to the lining of the gut wall. The specific fiber lignin is a powerful prebiotic, found predominantly in flaxseed and other edible seeds (such as strawberries and kiwi), and in lesser amounts in root vegetables and fruits. Subjects suffering from irritable bowel syndrome treated with a lignin-like supplement reported significant improvements in their symptoms, including flatulence, bloating and stool consistency.2

Psyllium seed and chia seed, a commonly recommended addition to popular detox diets, contains lignins as well as mucilaginous fibers that work as natural laxatives. These same fiber properties are found in beans. When using a psyllium supplement, it is very important to drink plenty of fluids to avoid stool compaction. Thus, you have the powerful effect of a liquid fast combined with psyllium seed supplements. You will certainly feel lighter after a few days of this regimen. But if you include a variety of high fiber foods in your diet every day, you’ll always be light on your feet.

Detox Diets - Myths vs. Reality

Yay or Nay to Juicing?

The most important nutrient is water. When you follow a liquid diet of water and juice, you are keeping yourself well hydrated, something you probably don’t normally do quite as well. Right away you’ll feel the beneficial effects. While you can’t flush fat out of your body, staying well hydrated cleanses the natural filtration system in your body: your kidneys. It also boosts the function of your liver, the real detox organ in your body.

Fruit and vegetable juices are concentrated sources of nutrients and plant products. These natural biochemicals may prevent cancer development (carcinogenesis) by interfering with detrimental actions of mutagens, carcinogens and tumor promoters, some of which can come in from our contaminated environment. In fact, some of these products may actually detoxify cancer-causing compounds and tumor promoters. For example, glucaric acid, found in high amounts in apples, broccoli, Brussels sprouts, cabbage and bean sprouts, may help to control and even prevent cancers by inhibiting beta-glucuronidase, an enzyme that can promote cancer.3

Juicing with vegetables can be a great way to enjoy a lot of vegetable nutrition in a small amount of time, but the drawback is that you consume less fiber. Whole foods give you greater purification power. Juicing with fruits is also a compact way of getting those nutrients, but it increases sugar intake dramatically. While you might take a whole day to eat five servings of fruit, you can easily consume five servings of fruit juice in one sitting. Despite the natural source of sugar, it is still a stressful jolt to your system. It is ideal to eat whole foods. Juice occasionally if you enjoy it, with an emphasis on vegetables rather than fruits.

Purification Ritual Reality

Numerous enzymes produced naturally by the body work non-stop to purify our cells. A plant-based diet rich in deeply colored vegetables and fruits supports this activity. Staying well hydrated keeps all your cells at functional capacity, and helps flush toxins from cells and organs quickly. Diets that provide adequate proteins and carbohydrates to build the enzymes and fuel metabolism, and at the same time are low in added sugars, refined carbohydrates, and saturated fats to limit inflammation, are the best purification optimization rituals.


Bok choy
Brussels sprouts
Mustard greens
Red grapes
Winter squash
Sweet potatoes
Flaxseed (ground)
Psyllium seed
Chia seed
Extra virgin olive oil
Fish oils
Lean protein
Whey protein


1. Vieira AT, Teixeira MM, Martins FS. The role of probiotics and prebiotics in inducing gut immunity. Frontiers in Immunology December 12, 2013 | doi: 10.3389/fimmu.2013.00445

2. Silk DBA, Davis A, Vulevic J, Tzortzis G, Gibson GR. Clinical trial: the effects of a trans-galactooligosaccharide prebiotic on faecal microbiota and symptoms in irritable bowel syndrome. Alimentary Pharmacology & Therapeutics Published online ahead of print, Early View, December 2008

3. Hanausek M, Walaszek Z, Slaga TJ. Detoxifying cancer causing agents to prevent cancer. Integrative Cancer Therapies 2003;2(2): 139-144