Is it me, or has there been a lot of press recently about what can be done to help preserve our mental faculties as we age? Just this week, for instance, saw the publication of a study in the American Journal of Medicine which found that individuals drinking fruit or vegetable juice three or more times a week, has a 76 per cent reduced risk of developing Alzheimer’s disease compared to those drinking such beverages less than once each week. One potential explanation for this explanation concerns damaging destructive molecules called free radicals, which are formed in the body as a natural by-product of metabolism, but are also implicated in chronic disease processes including heart disease, cancer and dementia. Fruit and vegetables are rich substances called ‘antioxidants’ which have the capacity to combat free radicals, which helps to explain, at least in part, how the drinking of fruit and vegetable juices might help us keep our mental edge as we age.
However, before we all go rushing to stock up on our supply of cartooned O.J., I feel a word of caution is warranted. Juices, particularly fruit juices, contain a hefty dose of sugar ” generally a similar concentration to those found in soft drinks such as cola and lemonade. I’m not for one moment comparing fruit juice with soft drinks ” obviously are way superior in that they are derived from fruit (a generally nutritious food) rather than being a chemical conglomeration of refined sugar and additives, perhaps with a bit of caffeine thrown in for good measure. However, the sugar concentration of fruit juice can cause blood sugar levels to sky-rocket, which can have a number of unwanted effects in the long term which include fatigue and hunger (typically 2-3 hours after ingestion as blood sugar levels plummet after their initial high) and in the long term may induce biochemical changes which predispose to issues such as weight gain and type 2 diabetes. Plus, fruit and vegetable juices will lack some of the nutritional value to be had from eating WHOLE fruit and veg. For more details about this, see the related article:
The bottom line is that to get the very most fruit and vegetables have to offer, eat them in their whole, un-juiced form. And if you are going to drink juice, my advice is to dilute half-and-half with water. This makes them must less sugary, and reduces the risk that drinking them will lead to blood sugar fluctuations that can have adverse effects on health. If you don’t like the taste of diluted juices, one option is to ensure the juice is diluted after, if not before, drinking. This means taking a slurp of water for each one of juice – simple, but effective.
Dai Q, et al. Fruit and Vegetable Juices and Alzheimer’s Disease: The Kame Project The American Journal of Medicine 2006 119 (9) 751-759
Observer Column 29th September 2004
In previous columns I have been overflowing with enthusiasm for the benefits to be had from drinking water. Many individuals find that keeping fluid levels topped up can stave off feelings of 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 very pleased to learn that the Government has recently 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. It seems allowing access to water during lessons could well encourage fluid thinking in our kids.
I note that another of the Government’s recent recommendations concerning liquid refreshment is for fizzy drinks in school vending machines to be replaced with fruit juice. While juices derived from fruit obviously offer better nutrition than sugar-charged or artificially-sweetened soft drinks, there are other things about them that does not whet my appetite. For instance, in the juicing a fruit a degree of its nutritional goodness (such as a good deal of its fibre and a proportion of its nutrients) get left behind. Also, most fruit juices are dehydrated, rehydrated and pasteurised prior to packaging. Overall, such processing is only likely to detract from the nutritional benefits offered by whole fruit.
Juiced fruit typically contains a blend of fructose, sucrose and glucose which, together, give it a sugar concentration that is very similar to that of regular soft drinks. Such sugariness, coupled with an acidic nature, has caused fruit juice to be cited as a risk factor for both dental decay and a wearing away of tooth enamel known as dental erosion. Once swallowed, the high sugar content of fruit juice can pose problems for the lower reaches of the gut too. 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 fruit juice may pose other hazards by stimulating the production of insulin – a hormone which increases the production of fat in the body, 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 some concern that fruit juice consumption may displace other more nutritious foods from the diet, increasing the risk of malnutrition. One study published in the journal Pediatrics found that young children drinking more than 360 mls of fruit juice each day were prone to short stature and obesity.
While I do not think that fruit 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. This will help to reduce any undesirable effects that might be inflicted by sugary load found in fruit juice. While such drinks may have a healthy image, a closer look reveals some juicy details that some may find quite unpalatable.