Wednesday, January 28, 2009

Sweeteners and your waist

They are called non-nutritive sweeteners (NNS) or intense sweeteners, although you and others probably still call them artificial sweeteners. Some of you will recall Tab and Tresca, soft drinks from the 1970s with saccharin or cyclamate in them. You only drank them as a form of punishment or if you had diabetes and were told to stick to sugar-free drinks.

Diet revolution of the 1980s
In 1985 aspartame (or Nutrasweet) was approved for use in Australia and the diet drinks tasted a whole lot better, as did other foods in which a sweetener replaced sugar. This was a time when sugar was listed under “Evil” in encyclopaedias (along with Hitler, nuclear bombs and disco music). Many people chose to drink diet drinks and anything hinting at no-added-sugar because this was seen as a sensible way to eat less kilojoules and remain lean.

A US survey in 1986 showed that those consuming the NNS were a wee bit chubbier than those that didn’t, speculating that NNS caused weight gain. Of course, you all know that surveys can only show associations and not cause and effect. When the survey was looked at again then it was equally likely that chubby people consumed more diet products because they wanted to get leaner. Since then, there has been little evidence that eating NNS causes weight gain or even helps much in weight loss.

Diet food compensation
A review of the evidence did suggest that NNS consumers may eat fewer kilojoules. One theory to explain this is that NNS trick the brain into thinking it has had food and shouldn’t feel as hungry, thereby leading to less food being eaten. People ate around 5-15% fewer kilojoules with diet products under test conditions, but there is little support that NNS use helps with weight control in free-living humans. One reason is that some people use diet products as a compensatory mechanism to offset a high fat food they may have eaten, so it’s no surprise if they don’t lose weight.

What does it all mean?
There is no compelling evidence that NNS themselves help people lose weight or maintain a healthy weight. Although a diet drink, for example, substituted for a regular sugared drink may be helpful to the weight conscious, the best advice we can give in the foreseeable future is: eat well, don’t eat too much, be active and ignore diet advice given on daytime TV (see non-story below).

Reference: American Journal of Clinical Nutrition 2008; 89: 1-14

Yet another story you won't read in 2009

Oprah Winfrey has declared that 2009 is the year she will stay fat. The high-profile TV personality has made it clear that she won’t be going on a diet in the next 12 months and neither will she be interviewing her previous health gurus on her top-rating show.

“If I brought all the kilos I’ve lost and gained in the last decade onto the television set we would need one of those NASA trucks for moving rockets. I’m going to do what I think every other fat person should do, and that is, give up”.

Health authorities have responded with dismay, saying that it is undermining their weight loss message, urging people to get psychologically distraught about their weight. “There goes our poster girl” said Laura Lipid who runs the Starvation to Salvation studio in North Sydney. “We loved it when Oprah looked super trim. We had a role model of note”.

When asked whether she would continue to endorse the health gurus she has promoted to stardom over the years, Winfrey said that health gurus are like tissues – keep them in your bag until needed and use them once before disposing.

“This has been a very liberating decision, and to make it in January means that I have nearly a year to tell the world that Dr Phil made me fat. That should dampen his book sales for a while. You didn’t buy a diet book by Dr Phil did you?” chuckled Oprah.

Winfrey denied that this was all a stunt sponsored by a major wide-screen television company.

Wednesday, January 14, 2009

Another story you won't read in 2009

In a rare moment of unity, both of Australia’s major current affairs programs, Today Tonight and A Current Affair, have declared they won’t be screening any weight loss stories during the year. This will be a shock to many as, in 2008, magical weight loss contributed 28% of all stories, ahead of shonky builders and car dealers (24%), and amazing beauty therapies (19%).

“To be honest, we have known for years that virtually every weight loss program we have covered has been unhealthy and untenable”, admitted Today Tonight producer Charles Chicane. “A couple of times we have followed up on these people and the company has either gone out of business or the interviewee is now a good 40kg heavier. We never, ever do a follow-up story. It’s an unwritten law”.

There has been an outcry from weight loss and supplement companies around the country.

“Current affairs programs have been the best free advertising we ever got ” said Martin Mountebank, President of the False Hope Institute. “These stories have given a real boost to sales over the years. Just because nearly every person regains their lost weight doesn’t mean that someone out there has not benefited over the years”.

The gap in programming will be hard to fill admits Chicane. “Look, we will have to fill the gap left by weight loss programs going forward, but I’m certain we can come up with stories that have equal merit. Only yesterday I saw someone wearing a red tie with a pink shirt. That’s just one of the issues we face today”.

Both program producers agreed it would change current affairs forever. “If cosmetic surgery is ever proven to be an expensive and egocentric attempt to distract people from a vacuous and unfulfilling life then we will probably drop those stories too” said Chicane.

Red wine vs white wine

Bottle of wine, fruit of the vine

It was Dr Serge Renaud who popularised the term “French Paradox” in 1992. The French eat more saturated fats than many other western nations, yet have a lower rate of heart disease. The attractive concept that wine could reverse the effects of a fatty diet has been the justification of many who enjoy a wine.

Red vs white
So begat to ongoing discussion of why wine may offer some health benefits. Was it the alcohol or the antioxidants? Could it even be that wine lovers were fitter and more likely to embrace moderation, or was it a quirk of statistics because French wine lovers were more likely to die of alcohol-related cancers or in car accidents, so it made sense that fewer got around to dying of heart disease?

Like all the big questions in health, the answer lies in a myriad of possibilities, and the distillation of the data usually suggests that some alcohol is better than none or lots. There is broad agreement that 1-2 standard drinks a day, no more, has life-enhancing prospects. (Note: I will always say that, even if the evidence changes).

An argument for white wine
Grape skin is included in the production of red wine, contributing to its resveratrol content and other antioxidants linked a reduction in heart disease. Even though white wine doesn’t have resveratrol (as no grape skin is included in the wine making), there may be other components in white wine that protects the heart. There is increasing evidence that tyrosol and hydroxytyrosol, both found in white wine (and in good olive oil), have an equally important role in protecting the heart.

A joint Italian and US study revealed what every white wine lover hoped. Researchers gave red and white wines to appreciative laboratory animals and found that both wines reduced the oxidative stress in the heart and lowered the inflammatory response. Here, I need to say that heart disease is an inflammatory disease causing atherosclerosis; it is not a build up of fat. Saturated fat, which raises LDL-cholesterol and cigarette smoke trigger the inflammatory response in the arteries, leading to artery narrowing and heart disease.

Both tyrosol and hydroxytyrosol seem to stop oxidation of LDL-cholesterol (the nasty cholesterol), stop platelet aggregation (nerdy term for blood clots that lodge in narrowed arteries), and reduce the inflammatory response leading to bad arteries. Anyway, the good news is that white wine seems to be protecting the heart in a similar fashion to red wine, using different compounds.

What does it all mean?
Enjoy the wine you enjoy. Red or white. Modest amounts. What may be of more critical importance to your health is the quality of the company you are with at the time of drinking.

Reference: Journal of Agricultural and Food Chemistry 2008; 56: 9362-9373