Tiredness and fatigue are such a feature of modern life that most of us don't even see it as a problem. But doctors and scientists are beginning to realise that general fatigue may be part of a continuum, leading ultimately to chronic fatigue and other debilitating conditions.
So, if you're tired all the time, your body may be trying to tell you to get more sleep, boost your nutrients, reassess your lifestyle and acknowledge when work or other commitments are just too much.
Most of us suppress these warnings with stimulants like caffeine or sedatives such as alcohol. Some turn to prescription or recreational drugs to help them cope. This may alleviate the problem in the short term, but drugs and alcohol often cause side-effects, dependency and, finally, more stress.
Many health conditions can cause fatigue (see box, page 2). In turn, each of these may be due to too much stress. In fact, poor health, stress and fatigue are so interlinked that stress has been called the number one cause of illness and disease. As much as 75-90 per cent of visits to healthcare professionals are related to stress.
Ayurvedic and Chinese medicine have a long history of using tonic remedies to bolster the body's adaptive mechanisms. Modern Western research has dubbed these tonic herbs 'adaptogens'-plants that can switch from stimulant to sedative, according to what the body's needs, thus increasing resistance to stress (Altern Med Rev, 2001; 6: 293-302). A good example of is Panax ginseng, which can raise or lower blood pressure accordingly.
Individual adaptogenic herbs may also be anti-inflammatory and immune-boosting. Others protect the liver and heart, or revitalise the nerves. In many studies, adaptogens have proved capable of protecting against cancer, reducing the side-effects of chemotherapy, and increasing resistance to radiation and chemical carcinogens. They can also help fight fatigue caused by health problems as well as general fatigue in otherwise healthy people.
In reviewing the evidence for 'energy-boosting' herbs, we found that much of this evidence-even for ginseng-is from animal studies, leaving us none the wiser as to their effects in humans.
When selecting a botanical remedy for fatigue, it's worth remembering that none of them produce 'energy' because none has calories. Also, herbs containing caffeine such as guarana may actually be debilitating if taken in large amounts over the long term. Caffeine can overstimulate the adrenals and increase levels of stress hormones like cortisol. High cortisol levels can compromise immune function and the body's ability to fight infection.
Of the 50 or so species of Rhodiola, it is only Rhodiola rosea, grown widely throughout the northern hemisphere, that is used medicinally. Rhodiola was brought to public attention by Soviet-era scientists and can benefit conditions such as decreased work performance, loss of appetite, mood changes such as irritability, poor sleep, headache and fatigue due to excessive activity, mental fatigue and viral infections. Supplementation can significantly improve the performance of physicians working the night shift (Phytomedicine, 2000; 7: 365-71) and students' exam scores (Phytomedicine, 2000; 7: 85-9).
Rhodiola has a more stimulating effect at lower dosages, and a more sedating effect in higher amounts.
No side-effects or interactions have been reported. Animal tests indicate that it has low toxicity, and a huge margin of safety at the recommended dosages.
Panax ginseng ****
Ginseng's main active ingredients-ginsenosides-are believed to counter stress, and enhance mental and physical performance. Its other constituents, such as panaxans, may help lower blood sugar while its polysaccharides (complex sugars) are thought to support immune function (Biol Pharm Bull, 1993; 16: 1087-90; Immuno-pharmacology, 1997; 35: 229-35).
The immunostimulant effects of Panax support the function of the hypothalamic-pituitary-adrenal axis, the body's hormonal stress system (Quart Rev Nat Med, 1996; Summer: 95-7). In theory, Panax gin-seng may help those with chronic fatigue.
Together with vitamins and minerals, 80 mg/day of ginseng reduced fatigue in adults (Phytother Res, 1996; 10: 49-53), while 200 mg/day improved blood sugar levels in type 2 (non-insulin-dependent) diabetics (Diabetes Care, 1995; 18: 1373-5).
Asian ginseng may also aid sperm count and motility (Panmineva Med, 1996; 38: 249-54), and 900-1800 mg/day improv-ed symptoms of erectile dysfunction (Int J Impotence Res, 1995; 7: 181-6; J Urol, 2002; 168: 2070-3).
Panax ginseng is a powerful stimulant and some herbalists believe it may be too strong for women (for whom Siberian ginseng may be more suitable). Panax should be taken for six to eight weeks, with two weeks off; it is not recommended for pregnant/nursing women or those with high blood pressure.
Of the pepper family, this herb (Withania) grows throughout India and Africa. Its active compounds-withanolides-are steroidal and similar to the ginsenosides in Asian (Panax) ginseng. Indeed, ashwagandha is also known as 'Indian ginseng'.
Animal findings suggest that it stimulates immune cells such as lymphocytes (Phytomedicine, 1994; 1: 63-76), inhibits in-flammation (Indian J Exp Biol, 1981; 19: 245-9) and improves memory (Phytother Res, 1995; 9: 110-3). These effects all support the traditional use of ashwagandha as a tonic or adaptogen, though human studies would be more reassuring.
No significant adverse effects or drug interactions have been reported. It is used safely by children in India, though its use in pregnancy/breastfeeding has not been tested.
This plant is a native of northern and northeast China, and adjacent regions of Russia and Korea. Its main constituents are lignans (schizandrin, deoxyschizandrin, gomisins and pregomisin) found in the seeds of the fruit. Modern Chinese research suggests a protective effect of these lignans on the liver and immune system (Planta Med, 1995; 61: 398-401), so it may be useful for chronic viral hepatitis.
An adaptogen similar to Panax, but milder, laboratory tests suggest it may boost work performance and strength, and reduce fatigue. Studies in horses suggest that it can increase stamina, speed and concentration (Phytomedicine, 1996; 3: 237-40; Fitoterapia, 1994; 65; 113-8), but this may not necessarily apply to humans.
Side-effects are not common, but may include stomach upset, a loss of appetite and skin rash.
Siberian ginseng ***
Laboratory studies show that Siberian ginseng (Eleutherococcus senticosus) contains antioxidants, cancer inhibitors and stimulants of the immune and pituitary-adrenal hormone systems (J Ethnopharmacol, 2000; 72: 345-93; Phytother Res, 2000; 14: 30-5; J Ethnopharmacol, 1984; 10: 235-41). It may also have a role in helping the liver get rid of harmful toxins (Br J Phytother, 1991; 2: 61-71).
Most of our knowledge of the adaptogenic effects of this herb in people comes from studies carried out in the former Soviet Union (Econ Med Plant Res, 1985; 1: 156-215). The findings of these studies are almost universally positive whereas Western data are less definitive. Despite the widespread use of this herb, in fact, there is no consensus of study data.
On the plus side, adverse effects are rare, and it appears to enhance mental acuity and physical endurance, at least in athletes, without the letdown that comes with caffeinated products. Siberian ginseng may also be useful as a preventative during the colds/flu season.
The downside is that, like Panax, it should be taken for short periods (six to eight weeks) followed by a two-week break; otherwise, its beneficial effects may be lost.
This plant (Paullinia cupana) is an evergreen vine from Brazil. Guarana gum or paste is derived from the seeds and used in herbal preparations.
Many claims have been made for its effectiveness in relieving fatigue, but few studies have been done to support them. So far, two clinical trials have found no significant effects on thinking or mental function with guarana (Rev Paul Med, 1994; 112: 607-11; Rev Paul Med, 1996; 114: 1073-8).
While its proponents claim that guara-na is 'rich' in nutrients, in fact, caffeine and other stimulants (theobromine and theophylline) are its main active ingredients. The effects of caffeine are already well known, and include stimulating the central nervous system, increasing metabolic rate and having a mild diuretic effect. It is also claimed that the caffeine in guarana is released more slowly than it is from coffee, but the results of one animal trial suggest this is not the case (J Pharm Pharmacol, 1992; 44: 769-71).
Guarana also contains tannins, which may prevent diarrhoea-at least in animals. As with any caffeinated product, guarana in excess may cause insomnia, trembling, anxiety, palpitations and urin-ary frequency. It should be avoided during pregnancy/breastfeeding.
Kelp-more precisely, bladderwrack-is a type of brown algae (seaweed). Its three main active ingredients are iodine, alginic acid and fucoidan. Iodine is needed for maintaining normal thyroid function. Those whose dietary iodine is low may find kelp helpful for conditions such as an underactive thyroid or goitre.
Alginic acid is a dietary fibre that can, in theory, relieve constipation and diarrhoea. In the test-tube, alginic acid can inhibit HIV (J Nat Prod, 1993; 56: 478-88), but there's no human data. In animals, it can lower LDL ('bad') cholesterol (Phytother Res, 1996; 10: 647-50).
Fucoidan is a dietary fibre high in sulphur. In laboratory and animal studies, it also lowers LDL and blood glucose levels (Phytother Res, 1996; 10 [suppl]: S184-5), and has anti-inflammatory, blood-thinning and antibacterial actions (Immunol Cell Biol, 1994; 72: 367-74; J Biol Chem, 1989; 264: 3618-23; Rev Esp Fisiol, 1984; 40: 227-30).
Kelp can also help lengthen menstrual cycles and reduce circulating oestrogen (BMC Comp Alt Med, 2004; 4: 10).
In short, this seaweed is full of theor-etical promise. However, if you are ingesting adequate iodine from your diet, kelp may not be necessary or wise, as it may overstimulate the thyroid.
In Ancient China, this mushroom was used to strengthen the body after exhaustion or a long-term illness, and for impotence, neurasthenia and backache. Today, more than 10 related species, as well as artificially cultured mycelia, are used in commercial preparations. Cordyceps sinen-sis, C. ophioglossoides, C. capita and C. mili-taris are the most commonly used species in supplements.
Cordyceps mushrooms contain a wide variety of potentially important consti-tuents. A number of studies indicate that they may have anti-cancer, immune-boosting and antioxidant effects (Chin Pharm J China, 2001; 36: 738-41; Ann NY
Acad Sci, 2001; 928: 261-73; Phytother Res, 2000; 14: 647-9). What's more, there are clinical trials that support the effectiveness of Cordyceps particularly for liver, kidney and immune-system disorders.
Sadly, studies into its medicinal effects are inconclusive because many of them were carried out in animals or test tubes, or used such different Cordyceps species, preparations and doses that it is difficult to compare results. Some also used injected extracts rather than oral supplements.
Nevertheless, Cordyceps has a long history of use as a food and is generally safe.
What causes fatigue?
There are dozens of different causes of daily fatigue, so you may need more than one method to manage it. Adaptogenic herbs are best for those whose fatigue is stress-related. However, as some of them can interact with conventional medications, always speak to your GP before combining herbs and medicines.
o Sleep disturbances: not enough or too much sleep, sleep apnoea (regular blocking of airways during sleep), shift work (changing shifts, night shifts), alcohol
o Heart problems: high or low blood pressure, arrhythmias (heartbeat irregularities), angina and other heart muscle dysfunctions), congestive heart failure
o Respiratory problems: asthma, allergies, chronic bronchitis, emphysema
o Nutritional disorders: underweight or overweight, vitamin deficiency (thiamine, B12, B6, folate, vitamin C)
o Electrolyte disturbances: low potassium, low magnesium, low or high calcium, low sodium
o Endocrine disorders: low or high blood sugar (diabetes), underactive or overactive thyroid, low cortisol (Addison's disease), high cortisol (Cushing's disease)
o Gastrointestinal disorders: gastroesophageal reflux disease (GERD), peptic ulcer
o Chronic disease: urinary tract infections, hepatitis, mononucleosis, chronic fatigue syndrome, anaemia, HIV/AIDS, tuberculosis, cancer
o Connective-tissue disorders: osteoarthritis, rheumatoid arthritis, systemic lupus erythematosus (SLE), fibromyalgia
o Psychological conditions: depression, anxiety, grief, stress
- for blood pressure : beta-blockers, calcium antagonists, diuretics, ACE inhibitors
- for mood disorders : antidepressants, antipsychotics, anxiolytics such as benzodiazepines (e.g. Valium) and imidazopyridines (e.g. Ambien)
- narcotic (opioid) painkillers : acetaminophen (paracetamol)/codeine (Tylenol with Codeine), hydrocodone/acetaminophen (Vicodin), oxycodone/acetaminophen (Percocet), propoxyphene/acetaminophen (Darvocet)