January is typically a time when many of us attempt to purge ourselves of the internal contamination and external baggage stockpiled at the tail end of last year. Those seeking a decent 'detox' will do well to drink plenty of water, one effect of which is to assist the flushing out of bodily pollutants via urine and sweat. Water purists usually recommend still rather than sparkling water. However, a recent study suggests that fizzy water may sometimes be healthier.
The research, published in the Journal of Nutrition, was designed to assess the health effects of sparkling and still mineral water in a group of women. The participants were asked to drink one litre of either sparkling or still each day for two months, followed by two months on the other water. During the study, the participants underwent a number of tests including blood-pressure checks and measurement of a variety of blood components, including cholesterol. The drinking of sparkling water brought about significant reductions in the level of low-density lipoprotein (LDL) cholesterol (a risk factor for heart disease), as well as a significant increase in levels of high-density lipoprotein (HDL) cholesterol (generally taken to reduce heart-disease risk). These and other biochemical changes induced by drinking sparkling water were estimated to reduce the women's risk of developing heart disease over the next decade by a third.
What it is about sparkling water that accounts for its seeming heart-healthy properties is not known for sure, though the explanation is unlikely to lie in the bubbles. More likely, the benefits of the water used in the study are related to its high mineral content. The fizzy stuff was particularly high in sodium - generally regarded as undesirable on account of its ability to boost blood pressure. However, studies show that low-sodium diets may increase cholesterol levels. This throws up the possibility that the sparkling water's relatively high sodium content might have played some part in its apparent ability to quell unhealthy cholesterol.
Interestingly, the Journal of Nutrition study found that the drinking of the sodium-rich mineral water did not lead to any increase in blood pressure. One reason for this is that sparkling waters tend to be rich in bicarbonate, which can help balance sodium's negative effects. My belief is that individuals keen to limit sodium in their diets need concern themselves less about foods and drinks that contain this mineral naturally, than processed foodstuffs that have had it added (often in considerable quantity) by food manufacturers.
Dear John
I take a statin drug to reduce my cholesterol level and was interested to read your article regarding the ability of these drugs to reduce levels of coenzyme Q10 in the body and cause fatigue. I had previously noticed some unusual tiredness, so started taking 60mg of coenzyme Q10 each day. Despite some scepticism, this has given me a new lease of life, but my cholesterol level has gone up from 5.8 to 6.4. Could coenzyme Q10 be responsible?
NR Gillhespy
There is not much research on the effects of coenzyme Q10 supplementation on cholesterol levels. However, one study (in the journal Molecular and Cellular Biochemistry in 2003) states that 120mg of coenzyme Q10 given each day for a year brought about a significant reduction in the levels of total and low-density lipoprotein (unhealthy) cholesterol as well as an increase in the level of high-density lipoprotein (healthy) cholesterol. But this same study found that supplementation with coenzyme Q10 was associated with a significantly reduced risk of cardiovascular events such as non-fatal heart attacks and strokes.
· If you have any issues you would like Dr Briffa to address in his column, please email him on john.briffa@observer.co.uk. Please note that Dr Briffa cannot enter into any correspondence. You can also visit drbriffa.com. Before following any recommendations in this column, you should consult your own medical adviser about any medical problems or special health conditions
Nutrition news
Allergic diseases, such as eczema, are common in children. There is some evidence that breast-feeding helps to prevent such allergic disease. One reason for this is that it delays the introduction of foods (such as cow's milk or cow's-milk formula) that may trigger the allergic process. However, there is some thought that specific agents in the breast milk may have protective potential. For instance, vitamin C causes known anti-allergic actions in the body, and low intakes of this nutrient are associated with increased risk of allergic disease.
In a study published this month in the European Journal of Clinical Nutrition, Finnish researchers assessed the relationship between the intake of vitamin C by breastfeeding mothers and the health of their babies. Higher concentrations of vitamin C in breast milk were associated with a 70 per cent reduction in risk of eczema. Researchers also found higher vitamin C intakes from the diet, and not from supplements, that translated into higher vitamin C concentration in breast milk. This study suggests that eating vitamin C-rich foods (citrus fruits, berries and green leafy vegetables) during breast-feeding may prevent allergic diseases such as eczema in children.
