In previous columns I have been overflowing with enthusiasm for the benefits of drinking water. Many individuals find that keeping fluid levels topped up can stave off fatigue and lethargy, and research has linked increased water consumption with a reduced risk of a range of conditions including heart disease and some forms of cancer.
I was therefore pleased that the government has recommended that school pupils be allowed to take water into the classroom. This move seems to have been triggered by British research which shows that even relatively mild dehydration may provoke headaches and irritability in children, and may cause brain power to dry up, too. Allowing access to water during lessons could well encourage fluid thinking in our kids.
Another recommendation is for fizzy drinks in school vending machines to be replaced with juice. While juices offer better nutrition than soft drinks, there are some things about them that do not whet my appetite. In juicing a fruit, a degree of its nutritional goodness (such as fibre and some nutrients) gets left behind. Also, most juices are dehydrated, rehydrated and pasteurised prior to packaging.
Juiced fruit contains a blend of fructose, sucrose and glucose which give it a sugar concentration that is very similar to that of soft drinks. Such sugariness, coupled with an acidic nature, has caused juice to be cited as a risk factor for dental decay and the wearing away of tooth enamel, or dental erosion. Its high sugar content can pose problems for the gut. Some children may be unable to absorb such a glut of sugar efficiently, which can lead to fermentation in the bowel with resultant bloating and wind. Also, excesses of sugar may draw water into the gut, precipitating diarrhoea.
Once absorbed from the gut, the sugar in juice may stimulate the production of insulin - a hormone which increases the production of fat, while at the same time stalling our fat-burning potential. Evidence is amassing that links the consumption of readily available sugar from food with a higher risk of obesity. Also, there is concern that juices may displace other more nutritious foods, increasing the risk of malnutrition. A study published in the journal Pediatrics found that young children drinking more than 360ml of fruit juice each day were prone to short stature and obesity.
While I do not think that juice should be forbidden for kids, it does seem as though there is good reason for them to consume it with some caution. I recommend a limit of a glass or two each day, and that this be diluted half-and-half with water. While such drinks may have a healthy image, a closer look reveals some juicy details that some may find quite unpalatable.
Dear John
I am 68 and have been on bendrofluazide for eight years for high blood pressure. Over the past year I have been getting bad cramp in my legs when I wake up. I recently stopped the bendrofluazide and the cramp went away. When I resumed, it came back again. Do you have any advice?
DC
Muscular cramp is often related to nutritional deficiency. Perhaps the two most relevant nutrients are potassium and magnesium - and bendrofluazide tends to deplete the body of these minerals. I suggest you up your intake of these nutrients. Potassium is found in all fruits and vegetables, with carrots and bananas being particularly rich in this mineral. Another good source is nuts, which also are rich in magnesium. Eat a few handfuls of unsalted nuts each day. The benefits of eating more foods rich in magnesium and potassium go beyond relieving cramp, as both are believed to reduce blood pressure. Also, fruit, vegetables and nuts have all been linked to a reduced risk of heart disease - the desired result of bringing your blood pressure down with bendrofluazide.
Nutrition news
Asthma is a condition that has a number of potential underlying causes, which include allergic reactions to food or external agents such as pollen, the house dust mite or other animals. Another potential factor relates to the type and amount of fat in the diet. Some evidence suggests that rises in the rates of asthma may be fuelled, at least in part, by a reduction in intake of omega-3 fats found in oily fish such as salmon, trout, mackerel, herring and sardine. Omega-3 fats have natural anti-inflammatory action in the body, an effect which is believed to help protect against inflammatory conditions such as asthma.
In a recent study published in the American Journal of Critical Care Medicine, researchers tested the effect of giving omega-3 fats to athletes suffering exercise-induced bronchoconstriction (EIB) - a type of asthma that comes on during exertion. The athletes consumed a total of 5.5g of omega-3 fats each day for three weeks. Compared to those taking placebo, those taking fish oil were found to have better lung function before, during and after doing exercise. This study provides further evidence that an increased intake of omega-3 fats benefit those suffering from asthma.
