Such claims, however, completely ignore the evidence showing that a variety of factors-including what we do, what we eat and what we're born with-can hamper our innate ability to detoxify. One such factor is our growing exposure to an ever-increasing array of toxic chemicals, but even
too much sugar in the diet can dramatically affect how our bodies handle toxins.
Most worrying, the science also shows that impaired detoxification may be responsible for a catalogue of common disorders, including cancer and Parkinson's disease.
Sceptical organizations such as the British quackbusting group Sense About Science claim that detox is pointless, as most chemicals don't accumulate in the body. However, mounting evidence shows that many of the 100,000 synthetic chemicals produced globally each year have not only made their way into our blood-streams, but also our body fat, where they then can accumulate for decades (Aust Fam Physician, 2007; 36: 1009-10).
Several studies, including those by the Environmental Working Group (EWG) in the US, and by WWF (World Wildlife Fund) and Greenpeace in Europe, have revealed that virtually all of us are walking around with a cocktail of man-made chemicals circulating in our blood, including compounds such as those used in the making of non-stick pans, fire-resistant sofas, baby bottles, the lining of tin cans and even long-banned pesticides (www.greenpeace.org/fragile).
Some of these agents have also been detected in human fat, supporting the idea that certain compounds do indeed build up or 'bioaccumulate' in the body. In 1982, the National Human Adipose Tissue Survey (NHATS) carried out by the US Environmental Protection Agency (EPA) found a total of 20 "toxic compounds" in 76 per cent or more of the fat samples tested. Five of these compounds-OCDD (a dioxin) and four solvents: styrene; 1,4-dichloro-benzene; xylene; and ethylphenol-were found in 100 per cent of the samples, and at alarmingly high levels.
These alone would give each person a toxic burden ranging from 57.4-6350 ng (nanograms) of toxins per gram of fat (Altern Med Rev, 2000; 5: 52-63). As the average American woman is 32 per cent body fat (Bailey C. The Ultimate Fit or Fat. New York: Houghton Mifflin Co, 1999), at a weight of 74 kg (163 lb), she would be carrying 0.15 mg/kg (0.33 mg/lb) of toxins in her fat alone. To put this in perspective, it is what is currently considered a moderate level of mercury in seafood.
Nevertheless, precisely what these toxins are doing to our health is not yet known, although a growing body of evidence implicates chemical exposures in a host of common health problems, including cancer, diabetes, infertility, obesity, and Alzheimer's and heart disease. As WDDTY has recently reported, some of the main culprits are pesticides, solvents, the plastics chemicals bisphenol A (BPA) and phthalates, flame-retardant chemicals (polybrominated diphenyl ethers, or PBDEs) and polychlorinated biphenyls (PCBs), formerly widely used indus-trial chemicals (see WDDTY vol 20 nos 2 and 8, and vol 19 no 9).
Not only have these chemicals been linked to disease in epidemiological studies-those looking for connec-tions between exposures and health effects in human populations-but there's also substantial animal and laboratory evidence to confirm that they can have harmful effects. In many cases, even low levels of exposure can be detrimental to health. BPA, for example, can cause substantial harm at levels below the supposedly 'safe' or reference dose of 50 mcg/kg/day (see WDDTY vol 18 no 8).
However, if we're all being exposed to toxic chemicals all the time, why aren't we all getting sick?
This is where detox comes into the picture. According to some scientists, whether or not we become ill from chemicals depends on how our body handles these compounds-in other words, our natural ability to effectively detoxify them.
What is detox?
Detoxification is essentially a waste-disposal system that the body has developed to rid itself of unwanted substances. This doesn't refer only to the environmental chemicals that are turning up in our tissues, but also to the chemicals generated by food intolerances and even by normal
bodily functions such as digestion. Indeed, nearly every molecule the body handles has to be eliminated from the system once it has served its purpose.
How the body does this is a highly complex process but, basically, it involves neutralizing the unnecessary agents so that they can be safely excreted from the body. As Dr Sidney Baker explains in his book Detoxi-fication and Healing (New Canaan, CT: Keats Publishing, 1997), the process involves two stages-functionalization and conjugation-or, more simply, phase-I and phase-II detoxification.
In phase I (functionalization), the waste chemicals need to become "activated" or made "sticky", so that they are easy to collect. A family of enzymes called 'cytochrome P450' is responsible for this phase, which Baker likens to what happens when you "[rub] a balloon on your sweater". Such activation of these chemicals, however, makes them more dangerous than they were to begin with, which is why phase II is crucial.
Phase II (conjugation) of detox involves the timely appearance of 'carrier molecules' that, with the help of various enzymes, 'deactivate' the waste chemicals so that they can be safely transported away from the body. According to Baker, this is like "sticking the sticky trash to individually tiny, somewhat sticky trucks. When each activated toxic or leftover molecule is stuck to a carrier molecule, it becomes deactivated and more soluble in the water of your blood or bile so that it can leave your body via your kidneys or intestine".
This natural detoxification system is one of the reasons why sceptics claim that the various commercial detox products and therapies available are useless. Indeed, in the leaflet Debunk-ing Detox, Sense About Science argues that you don't have to do anything to support your eliminatory organs-specifically, the kidneys, liver and digestive system-unless you have consumed a dangerous dose of some substance or you have been poisoned and, therefore, require a stomach pump or dialysis.
However, the problem with claims like this is that not everyone's bio-chemistry is the same. As the research shows, our individual detoxification systems are as unique as fingerprints and influenced by a variety of factors. While some people are highly efficient at eliminating harmful chemicals, others are not, which can lead to their systems becoming clogged up.
Genomics-the new, highly detailed study of genetics-has revealed that some individuals have genetic differences in their livers involving either the phase-I or phase-II detoxi-fication pathways, or both, that prevent them from adequately and efficiently clearing environmental contaminants from their blood-streams (Altern Complement Med, 2001; 7: 227-32).
According to Dr Damien Downing, a clinician who has worked in the field of nutritional and environmental medicine for over 25 years, around
50 per cent of us carry a variation (a 'polymorphism') of a gene known as CYP1A2, which codes for one of the most important phase-I detoxifying enzymes in the liver. This gene can greatly increase the activity of the enzyme which, in turn, can lead to the production of more free radicals than the body can handle. If, at the same time, there is also a reduction in the crucial phase-II enzyme glutathione S-transferase (GST), which is responsible for the final inactivation and removal of chemicals from the body, then there is even more stress on the bodily system.
"Having a common polymorphism in one of the several genes for this latter enzyme will greatly reduce your ability to inactivate and remove a range of molecules: pesticides; toxic metals; petrochemicals; antibiotics; hormones; even alcohol," explains Downing. "It is no great surprise that this will make you at least twice as likely to suffer allergic reactions-both to 'conventional' inhalants like pollen and to chemicals like second-hand tobacco smoke and exhaust fumes.
"Then imagine the impact of having polymorphisms in both these enzymes-which a significant percen-tage of the population do have-on your ability to handle chemicals."
Interestingly, several studies are turning up links between impaired detoxification and certain conditions, such as cancer, Parkinson's disease, fibromyalgia and chronic fatigue/ immune dysfunction syndrome (Altern Med Rev, 1998; 3: 187-98).
In one study carried out in Taiwan, women who carried a polymorphism of the CYP1A1 gene-involved in the metabolism of environmental carcinogens and oestrogen-were up to two times more likely to have breast cancer (Br J Cancer, 1999; 80: 1838-43). In Japan, the same polymorphism was associated with a threefold greater risk of lung cancer (FEBS Lett, 1990; 263: 131-3).
Similarly, researchers from the UK discovered that people with genetic variations that make them 'slow metabolizers' of toxins had a higher risk of Parkinson's disease (Mov Disord, 2000; 15: 30-5).
These genetic differences may also explain why some people have adverse reactions to pharmaceutical drugs while others don't (Clin Pharmacokinet, 2009; 48: 761-804).
In addition to genetics, our chemical body burden can also influence our ability to detoxify. Heavy exposure to environmental chemicals-perhaps related to our jobs, hobbies or where we live-can place considerable stress on our detox systems, causing them to not work properly. As Dr DeAnn Liska explains in a comprehensive review of detoxification enzyme systems, "Increased toxic load may lead to inhibition of detoxification of a number of compounds by simply overwhelming the systems and competing for detoxification enzyme activities" (Altern Med Rev, 1998; 3: 187-98).
Not surprisingly, even pharmaceutical drugs can contribute to the toxic load. A recent study found that high intakes of common drugs, including the painkillers naproxen and mefenamic acid, can lead to impaired detoxification of two potentially harmful environmental pollutants, nonylphenol and bisphenol A (Xeno-biotica, 2009 Nov 16; Epub ahead of print).
Although the study was conducted in rats and so may not apply to humans, it does suggest that people on long-term medication-a substan-tial chunk of the population-may not be able to detoxify efficiently.
An unbalanced diet-too much sugar or too little protein, for instance-can also affect our detox mechanisms (see box, page 8), as can our age and overall health status. Clearly, it's wrong to assume that everyone is capable of handling toxins efficiently, and it's likely that many of us can certainly use some extra help.
Detox as therapy
Is there any evidence that detox as a therapeutic approach actually works?
There's an abundance of detox products and programmes on the market-from juices and diets to supplements and tonics-all claiming to assist the body in the elimination of toxins. However, few of these have any scientific evidence to support their claims. Also, while there are hundreds of randomized controlled trials of drug and alcohol detox, there are no such trials of detox programmes focusing on the clearing of environmental toxins (Aust Fam Physician, 2007; 36: 1009-10).
Nevertheless, there is promising evidence, albeit often from animal studies, showing that various natural agents and methods can help to remove chemicals from the body (see box, page 9, and page 15).
What's more, there are several studies in humans suggesting that certain detox programmes can alleviate symptoms of chemical toxicity. Most of these are based on a detox programme controversially developed by Scientology founder L. Ron Hubbard. Originally designed to aid the removal of drugs from the body, the method is now also used to reduce levels of other fat-stored compounds, such as pesticides and industrial chemicals. The programme uses high-dose niacin along with other vitamins, minerals and polyunsatur-ated oils, in conjunction with physical exercise and extensive sweating induced by sauna baths. Each component is supported by scientific research and, although the method has been criticized (as has Scientol-ogy itself), the method does have evidence of working.
Recently, the programme was used to treat rescue workers exposed to multiple toxins after the 9/11 World Trade Center disaster. Many of these workers had developed a range of health symptoms as a result of their rescue efforts. In one preliminary study, workers following the Hubbard regime significantly reduced their bodily burdens of polychlorinated biphenyls (PCBs), polychlorinated dibenzofurans (PCDFs) and polychlor-inated dioxins (PCDDs). In addition, as the authors reported, "Health symptoms completely resolved or were satisfactorily improved on com-pletion of treatment" (Chemosphere, 2007; 69: 1320-5).
In yet another study, this time a controlled trial of electronics workers occupationally exposed to PCBs and other industrial chemicals, the Hub-bard method led to significant PCB reductions in both blood and fat by 42 per cent and 30 per cent, respec-tively, in around half the patients. Also, all reported marked improvement in symptoms. In contrast, the controls saw an increase in PCB levels and no improvements in health (J Environ Sci Health Part A, 1990; 25: 731-51).
The Hubbard detox programme also proved successful in treating 14 fire-fighters who became ill after responding to a fire that involved transformers that were filled with PCBs. A battery of 22 neurophysiol-ogical and neuropsychological tests were carried out on these firefighters six months after the fire. The results revealed that all of these men were significantly impaired in both memory and cognitive function compared with co-workers from the same department who had not participated in fighting that particular fire. Following the detoxification treatment, however, marked improvements were noted in six of the 13 tests that had originally shown damage (Arch Environ Health, 1989; 44: 345-50).
A number of other studies, including case reports, cohort studies and non-randomized controlled trials, also suggest that the Hubbard detox programme can reduce the burden of various chemicals in the body as well as improve the associated health problems. The method also appears to be safe. An initial study reported that medical complications were seen in less than 3 per cent of the 103 participants, and included one case of pneumonia, one ear infection and one bout of diarrhoea over the three-week programme. Nevertheless, more sys-tematic and rigorously controlled trials are still needed to confirm its safety and efficacy (Aust Fam Physician, 2007; 36: 1009-10).
Detox: the reality
There's still a lot to learn about detox but, already, it's crystal clear that the sceptics have got it wrong. Everyone's innate detox systems are unique, and there's good evidence that our genes, lifestyles and even our diets could be dramatically affecting our ability to process toxins.
Crucially, too many poisons getting into the system could mean that not enough are getting out.
We are only just beginning to understand the impact that impaired detox has on our health and to figure out who needs help in detoxing. Nevertheless, the findings so far suggest that detox may be a valuable therapy, or preventative, for many of the diseases plaguing modern society.
Detox: what works?
Detox is about removing the toxins inside you and avoiding further exposures. As each of us has an innate-and unique-detoxification system, for best results, it's important to visit a qualified practitioner who can assess such individual factors as toxic load, food sensitivities and whether or not your digestive tract is functioning properly. In particular, those who have a serious medical condition such as heart disease-or any other illness-should not attempt to detox without supervision. For the rest of us, here's a general guide to what works.
o Exercise can boost the body's detox systems. Even a single session on an exercise bike can double your levels of detox enzymes (Life Sci, 1990; 47: 427-32).
In one trial involving 335 people, researchers used measured doses of caffeine and traced its degradation in the body by monitoring the amount of caffeine metabolites (breakdown products of caffeine in the body) found in the urine. After 30 days of aerobic exercise, the rate of caffeine degradation had increased substantially (Adv Exp Med Biol, 1991; 283: 407-11).
Fit and healthy people should aim to do 20-30 minutes of aerobic exercise (the kind that leaves you slightly breathless) three to five times a week, followed by a shower to prevent the reabsorption of toxins.
o Sauna baths increase sweating, thereby encouraging the elimination of heavy metals (Clin Chem, 1973; 19: 1288-92), toxic volatile hydrocarbons (Bol Asoc Med PR, 1991; 83: 321-4), PCBs (Arch Environ Health, 1989; 44: 345-50), pesticides (Townsend Lett Docs, 1992: 107: 470-8), prescription/recreational drugs (Beitr Gerichtl Med, 1990; 48: 45-9) and other toxins (Pol Tyg Lek, 1991; 46: 186-7).
Health-club saunas and steamrooms can work, but detox expert Dr Shideh Pouria, medical director of The Burghwood Clinic in Surrey, UK, recommends far-infrared saunas, which emit infrared radiant heat that is absorbed directly into the human body. Around 3-5 minutes every other day should benefit most people, but make sure you drink enough water to replace lost fluids, and always follow the session with a shower.
o Cruciferous vegetables such as broccoli, cabbage, cauliflower and watercress are rich sources of isothiocyanates, compounds that induce phase-II detox enzymes and boost antioxidant activity (Proc Natl Acad Sci U S A, 1997; 94: 10367-72). This might explain
why eating such vegetables appears to protect against cancer (Mutat Res, 2001; 480-1: 285-97). In one study, isothiocyanates helped to blunt the carcinogenic effects of cigarette smoke in rats. In humans (volunteer smokers), just chewing 2 oz of watercress at each meal for three days significantly increased detox of a nicotine carcinogen excreted in their urine (Adv Exp Med Biol, 1996; 401: 1-11). Aim to include a mix of organic crucifers (at least five servings) in your daily diet.
o Onions, garlic and leeks are also well recognized as detoxifying agents. As well as having antioxidant properties, they are known to contain organosulphur compounds, which are important inducers of phase-II enzymes (Clin Nutr Insight, 1997; 5: 1-4).
o Fibre is thought to benefit detox as it binds to toxins and aids their removal. Animal and test-tube studies show that dietary fibre, such as rice bran and spinach, can enhance the excretion of various environmental carcinogens, including polychlorinated dibenzofurans (PCDFs) and polychlorinated-p-dioxines (PCDDs) (J Nutr Biochem, 2005; 16: 50-8). However, such results may not apply to humans.
o Green tea is also an effective detoxifying agent-at least in animal studies. Liquid extracts of the tea at typical concentrations consumed by tea drinkers were shown to influence a crucial phase-II reaction in the liver, thereby aiding the metabolism of toxins into inactive, readily excretable molecules (Food Chem Toxicol, 1995; 33: 27-30). Although these results may not apply to humans, epidemiological studies have linked green tea consumption-usually about 3 cups a day-to reduced cancer risks in men and women. This may be partly due to the enhanced detoxification of carcinogenic substances by green tea (Altern Med Rev, 1999; 4: 360-70).
o Seaweeds and alginates. Chlorella algae can draw persistent chemicals such as dioxins out of the system and prevent their absorption in the stomach-at least in rats (J Nutr, 1999; 129: 1731-6).
In addition, in a study of pregnant women, those given Chlorella supplements had significantly lower levels of dioxins in their breast milk and cord blood, suggesting that the algae can reduce maternal transfer of these harmful chemicals to the fetus or nursing infant (Chemosphere, 2005; 61: 1244-55).
Similarly, eating seaweeds such as wakame, hiziki and kombu has been shown to speed up the excretion of dioxins stored-albeit again in rats (J Agric Food Chem, 2002; 50: 910-7). But bear in mind that anything that comes from the sea may be polluted, so be sure to choose products from a reputable manufacturer.
o Herbs and supplements. Milk thistle, vitamin C, alpha-lipoic acid, selenium and N-acetylcysteine have all been shown to increase body levels of glutathione, which is essential for phase-II detoxification (Alt Med Rev, 2000; 5: 133-43). Also, the Rasayanas, a group of Ayur-vedic herbal preparations, can enhance detox mechanisms (Am J Chin Med, 2002; 30: 155-71). For optimal dosages, consult a qualified practitioner.
o Avoidance. Minimizing your exposure to toxic chemicals is an important part of any detox programme. The WDDTY report Safe Living (lb12.95; available to download from www.wddtyhealthshop. com) provides useful pointers on what to look out for.
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