"Energy Drinks

There are now many energy drinks on the market, which are claimed to improve mood, health and performance. With advertisements which use words like "gives you wings", "gives the ultimate high" and claims to boost your immune system it's no wonder that the number of these drinks is growing.

The drinks contain a variety of ingredients with the main one being sugar. They may also contain ingredients such as caffeine, herbs, amino acids, guarana, vitamins and minerals.

Caffeine. The caffeine content in the drinks available varies from 30 to 80 mg per can, equivalent to one cup of tea or one cup of strong instant coffee. 40 mg caffeine can increase energy, alertness, concentration and enhance mood, depending on individual reactions to caffeine. But caffeine is not recommended for children and pregnant women. More than 100 mg caffeine daily increases the risk of miscarriage in the first three months of pregnancy. Caffeine can increase urination and lead to dehydration if consumed in large amounts. In some people, excess caffeine can also lead to heartburn, insomnia, migraine, heart palpitations and increased heart rate. Caffeine also reduces the absorption of calcium into the bones, increasing the risk of osteoporosis. There have been rare cases of death from the effects of caffeine due to the effects on the heart rate. It is recommended that we consume no more than 250 to 450 mg of caffeine per day.

Guarana is a naturally occuring substance which contains caffeine. 1 g of guarana contains about 60 mg caffeine, which is equal to that in 1 cup of instant coffee. Guarana reduces the effectiveness of the medication, warfarin, which is prescribed to reduce the risk of blood clots.

Vitamin A is has a valuable function as an antioxidant, helping to protect against heart disease and cancer.
Vitamin A is fat soluble, and is stored in liver and fat tissues of the body. The recommended intake of vitamin A for adults is 750 to 1200 micrograms daily. Large intakes of vitamin A over time can result in inflamed itchy skin, lethargy, nausea & vomiting, thinning of the hair, fragile bones in severe cases, haemorrhage & liver damage, and birth defects in pregnant women. These effects can occur at levels of 200 micrograms per kg of body weight i.e 10000 micrograms and upward. Some of these drinks contain 450 to 1000 micrograms per can. Given that 40 g carrots or 100 g pumpkin plus 100 g broccoli will provide 750 micrograms of vitamin A it is quite possible that regular consumption of these drinks in conjunciton with a healthy diet will provide very large amounts of vitamin A.

B vitamins are involved in the processing of energy but if your food intake provides sufficient amounts, more will not improve this function further. B vitamins are water soluble so are not stored in the body and excess is passed out in the urine. However one of the B vitamins, niacin, can cause flushing, burning, tingling, itching, redness at high levels.

Taurine is an amino acid which is found only in animal tissues, but its role in the body is not fully understood. Taurine is excreted in the urine in times of stress so there are claims that it has a detoxifiying role but there is no scientific evidence for this. There is no recommended intake for taurine as we manufacture our own. Taurine is present at levels of 1000mg per can in some drinks. There is no evidence for harm or safety of taurine at these levels.

Inositol is sometimes called Vitamin B3 but it is not an essential ingredient in our diets as the body manufactures it from glucose. It is part of the structure of cells, with high concentrations found in the heart, brain and liver. Inositol prevents fat accumulating in the liver. It is claimed that inositol helps to calm and settle. At very high levels (12 g per day), inositol may help people with depression or panic disorders at levels of 12 g per day. The drinks contain 5 to 50 mg per can. This level of supplementation is probably safe. It is found in liver, meats, milk, wholegrain cereals, nuts, fruits and vegetables.

Glucuronolactone is made from the breakdown of glucose by body. Some products claim that it is detoxifiying but there is no evidence for this or any apparent benefit. There is no evidence of danger but the drinks provide many times what you would normally get from food.

Coenzyme Q10. Coenzyme Q10 is needed for generating energy in all human cells, and has an antioxidant function. It is claimed to prevent many disorders, including aging itself. Some research suggests that it may be useful to treat heart disease although there is inconsistent data from studies. Coenzyme Q10 is manufactured by the liver and is found in many food, especially in meat and fish. The levels in the body decrease with age but that doesn't mean that more of it will reduce the effects of disease or age. There is no evidence to suggest supplements of coenzyme Q10 are of benefit to healthy people and there is much research to be done before conclusions can be drawn.

Ginseng. Ginseng is claimed to boost energy and athletic performance and supposedly can treat a wide range of disorders from the common cold to Alzheimer's disease. However the research done so far is poorly controlled and contradictory, giving no clear evidence of any benefit. Ginseng contains at least 13 different types of natural compounds called ginsenosides, in addition to other oils, sugars, fats, vitamins, minerals and plant hormones. It is unclear which of these if any provide benefit. There are different types of ginseng, and ginseng added to foods may be obtained from the leaves, roots or stems, each of which will provide different natural compounds. So the listing of ginseng as an ingredient does not represent a standardised amount of the natural compounds. Some products claimed to have ginseng actually contain very little ginseng, or even none in some cases. Ginseng has been reported to cause nosebleeds, high blood pressure, vaginal bleeding, breast tenderness, and headache in some people.

Gingko biloba. Claims are made that gingko biloba can support brain function by promoting the circulation and oxygenation of the blood flow to the brain. This has some basis and it is used in some countries to treat dementia. However the research has not been independently tested, and it is difficult to get a standardised amount in energy drinks. It can produce side effects including bleeding in the eye and bleeding after surgery. It can interfere with the function of medications such as aspirin and warfarin.

St Johns Wort is a herb which is used to calm and may be used to treat depression. It can reduce the effectiveness of medications including depression, hiv, blood clots, epilepsy. It can cause agitation when mixed with migraine tablets or anti-depressants and can reduce the effectiveness of some medications.

Mostly, the reason for including the above ingredients is simply marketing.

Naturally occuring substances such as guarana, ginseng etc are permitted to be added to foods without having to prove that they actually live up to the claims made for them. Labelling laws do not require them to state the amount of caffeine etc contained in the food, and the warnings if any about the presence of caffeine are often quite small and not readily seen. A better way to get an energy boost would be to eat a piece of grain bread with a banana, which would provide a sustained release of energy with plenty of vitamins, minerals and antioxidants. The sugar in these drinks would provide a quick fix which would soon be gone as the sugar is removed from the bloodstream. The risk of tooth decay is high as for normal soft drinks. Many of the ingredients added can interact with other drugs or medications and as the amount found in a food is uncertain, this may cause significant effects on the management of other conditions.