Saturday, March 24, 2007

Fertility clock may affect men

Prospective fathers should not leave it too long

WHEN it comes to fertility and the prospect of having normal babies, it has always been assumed that men have no biological clock. But mounting evidence suggests that as men get older, they face an increased risk of fathering children with abnormalities. Several recent studies are starting to persuade many doctors that men should not be too cavalier about postponing marriage and children.

Geneticists have been aware for decades that the risk of certain rare birth defects increases with the father's age. One of the most studied of these conditions is a form of dwarfism called achondroplasia, but the list also includes the connective tissues disorder, Marfan syndrome, and skull and facial abnormalities, such as Apert syndrome.

Some studies suggest that the risk of sporadic single-gene mutations may be four to five times higher for fathers who are 45 and older, compared with fathers in their 20s, says Joe Leigh Simpson, the president-elect of the American College of Medical Genetics. Overall, having an older father is estimated to increase the risk of a birth defect by 1 per cent, against a background 3 per cent risk for a birth defect, he says.

A recent study on autism produced striking findings about this perplexing disorder. Researchers analysed a large Israeli military database and found that children of men who became a father at 40 or older were 5.75 times as likely to have an autism disorder as those whose fathers were younger than 30. "Until now, the dominant view has been, 'Blame it on the mother,' " said Avi Reichenberg, the lead author of the study, published in The Archives of General Psychiatry. "But we found a dose-response relationship: the older the father, the higher the risk. We think there is a biological mechanism that is linked to ageing fathers." The study controlled for the age of the mother, the child's year of birth and socioeconomic factors, but researchers did not have information about autistic traits in the parents. [But see my skeptical comment about that study of Sept. 6th, 2006]

Another Israeli study on schizophrenia, using a registry of 87,907 births in Jerusalem between 1964 and 1976, found that the risk of illness was doubled among children of fathers in their late 40s when compared with children of fathers under 25, and increased almost threefold in children born to fathers 50 and older. "When our paper came out, everyone said, 'They must have missed something,' " says an author of the study, Dolores Malaspina, of New York University Medical Centre. But studies elsewhere have had similar findings, she says. "The fact it's so similar around the world suggests it's due to biological ageing."

Sceptics say the studies find an association but do not prove a causal relationship between an older father's genetic material and autism or schizophrenia, and note that other factors related to having an older father could be at play, including different parenthood styles. Another possibility is that the father's mental illness or autistic tendencies are responsible both for the late marriage and for the effect on the child. "'The problem is that the data is very sparse right now," says Larry Lipshultz, a past president of the American Society for Reproductive Medicine. "I don't think there's a consensus of what patients should be warned about."

Brenda Eskenazi, of the school of public health at the University of California, Berkeley, however, says men need to be concerned about their ageing. "We don't really know what the complete effects are of men's age on their ability to produce viable, healthy offspring."

Pamela Madsen, the executive director of the American Fertility Association says: "It takes two to make a baby, and men who one day want to become fathers need to wake up, read what's out there and take responsibility. Everyone ages. Why would sperm cells be the only cells not to age as men get older?"


Cocoa 'Vitamin' Health Benefits Could Outshine Penicillin

Ho hum! Another bright-eyed promise of a "natural" miracle

The health benefits of epicatechin, a compound found in cocoa, are so striking that it may rival penicillin and anaesthesia in terms of importance to public health, reports Marina Murphy in Chemistry & Industry, the magazine of the SCI. Norman Hollenberg, professor of medicine at Harvard Medical School, told C&I that epicatechin is so important that it should be considered a vitamin.

Hollenberg has spent years studying the benefits of cocoa drinking on the Kuna people in Panama. He found that the risk of 4 of the 5 most common killer diseases: stroke, heart failure, cancer and diabetes, is reduced to less then 10% in the Kuna. They can drink up to 40 cups of cocoa a week. Natural cocoa has high levels of epicatechin. [And they have a totally different lifestyle too]

'If these observations predict the future, then we can say without blushing that they are among the most important observations in the history of medicine,' Hollenberg says. 'We all agree that penicillin and anaesthesia are enormously important. But epicatechin could potentially get rid of 4 of the 5 most common diseases in the western world, how important does that make epicatechin?... I would say very important'

Nutrition expert Daniel Fabricant [Fabricant's doctorate is from the Center for Botanical Dietary Supplement Research of Chicago] says that Hollenberg's results, although observational, are so impressive that they may even warrant a rethink of how vitamins are defined. Epicatechin does not currently meet the criteria. Vitamins are defined as essential to the normal functioning, metabolism, regulation and growth of cells and deficiency is usually linked to disease. At the moment, the science does not support epicatechin having an essential role. But, Fabricant, who is vice president scientific affairs at the Natural Products Association [Is that another word for the Placebo Association?], says: 'the link between high epicatechin consumption and a decreased risk of killer disease is so striking, it should be investigated further. It may be that these diseases are the result of epicatechin deficiency,' he says.

Currently, there are only 13 essential vitamins. An increase in the number of vitamins would provide significant opportunity for nutritional companies to expand their range of products. Flavanols like epicatechin are removed for commercial cocoas because they tend to have a bitter taste. So there is huge scope for nutritional companies to develop epicatechin supplements or capsules. Epicatechin is also found in teas, wine, chocolate and some fruit and vegetables.



Just some problems with the "Obesity" war:

1). It tries to impose behavior change on everybody -- when most of those targeted are not obese and hence have no reason to change their behaviour. It is a form of punishing the innocent and the guilty alike. (It is also typical of Leftist thinking: Scorning the individual and capable of dealing with large groups only).

2). The longevity research all leads to the conclusion that it is people of MIDDLING weight who live longest -- not slim people. So the "epidemic" of obesity is in fact largely an "epidemic" of living longer.

3). It is total calorie intake that makes you fat -- not where you get your calories. Policies that attack only the source of the calories (e.g. "junk food") without addressing total calorie intake are hence pissing into the wind. People involuntarily deprived of their preferred calorie intake from one source are highly likely to seek and find their calories elsewhere.

4). So-called junk food is perfectly nutritious. A big Mac meal comprises meat, bread, salad and potatoes -- which is a mainstream Western diet. If that is bad then we are all in big trouble.

5). Food warriors demonize salt and fat. But we need a daily salt intake to counter salt-loss through perspiration and the research shows that people on salt-restricted diets die SOONER. And Eskimos eat huge amounts of fat with no apparent ill-effects. And the average home-cooked roast dinner has LOTS of fat. Will we ban roast dinners?

6). The foods restricted are often no more calorific than those permitted -- such as milk and fruit-juice drinks.

7). Tendency to weight is mostly genetic and is therefore not readily susceptible to voluntary behaviour change.

8). And when are we going to ban cheese? Cheese is a concentrated calorie bomb and has lots of that wicked animal fat in it too. Wouldn't we all be better off without it? And what about butter and margarine? They are just about pure fat. Surely they should be treated as contraband in kids' lunchboxes! [/sarcasm].

Trans fats:

For one summary of the weak science behind the "trans-fat" hysteria, see here. Trans fats have only a temporary effect on blood chemistry and the evidence of lasting harm from them is dubious. By taking extreme groups in trans fats intake, some weak association with coronary heart disease has at times been shown in some sub-populations but extreme group studies are inherently at risk of confounding with other factors and are intrinsically of little interest to the average person.