Over the weekend, I was reading about an Australian study in which individuals shopping on-line for food were able to be diverted away from foods rich in saturated fat by some nifty software that gives purchase-specific dietary advice. I like the idea of anything that gives individuals the opportunity to make informed eating choices more easily. The critical word here, though is ‘informed’.
This study, like thousands that have gone before it, focuses on saturated fat as the major dietary villain. Eat it, we are told, and can only help us down the path to obesity and clogged arteries. However, the fact that saturated fat is something we have probably been eating for all of our time on this planet suggests that we should be quite well adapted to it by now.
I’ve attached two pieces here that explore this phenomenon. The first looks at the relationship between dietary fat and body fat, and examines the effectiveness of the low-fat diet so often touted by health professionals with regard to weight loss. The second piece explores the relationship between saturated fat and heart disease. Read these pieces, and you may get the impression that saturated fat has been unfairly victimised. How could this be? My personal belief is that this has been a ploy by the food industry to divert our attention away from the rubbishy fats they serve us as ‘healthy’. I’m talking partly here about what are known as partially hydrogenated fats (which may contain the particularly nasty fats known as ‘trans’ fats) as well as a glut of refined vegetable oils, an excess of which have been implicated in cardiovascular disease and diabetes.
The bottom line is this ” if you want to eat healthily, you need to eat a diet based on primal foods (including fatty ones) in as natural and unadulterated form as possible (whatever the food industry would have you believe). Those interested in reading further regarding this concept might like to read the blog posted on 1st September 2006, which explodes the myth that margarine is better than butter.
Observer Column – 14th March 2004
In an effort to contain the ever-expanding levels of obesity in the UK, the Government is considering levying a tax on unhealthy foods such as those rich in fat. Perhaps not surprisingly, the so-called ‘fat tax’ has attracted some criticism from those keen to stay out of the clutches of the nanny state. Also, some quarters in the nutritional establishment have questioned how effective punitive pricing of fattening food would be in changing our eating behaviour, and have suggested subsidising more nutritious fare instead. It is likely that a strategy that makes healthy food more accessible to all is likely to attract widespread support. However, I wouldn’t bank on the Government, and Gordon Brown in particular, being too keen to fork out for such a food subsidy scheme.
Whatever reservations there may be about the use of a fat tax in an assault on obesity, received wisdom is that it will at least tip the scales in our favour. After all, studies show that rates of obesity are higher in countries that consume plentiful amounts of fat (such as USA, the UK and Australia) compared to those where fat intake is lower (such as India and China). However, some scientists have pointed out that the disparity in rates of obesity between different countries may have other explanations. Higher levels of activity and more limited access to food, for instance, may explain why individuals living in poorer countries appear to be relatively immune to the problems of overweight and obesity.
A more accurate picture of the broad relationship between fat in our diets and fat sequestered in our bodies can be gained from studies comparing countries of similar economic development. In one such study published in the European Journal of Clinical Nutrition, the proportion of calories contributed by fat was found to range from 25 – 47 per cent across 18 countries. However, this wide variation in fat intake appeared to have no bearing on body weight in men. Even more surprising was the finding that, in women, higher levels of fat consumption were clearly associated with a reduced risk of excess weight. This evidence should perhaps give the Government pause for thought before it ploughs ahead with its plans to slap a tax on fat.
Interesting though such research is, it is not as good for predicting the likely effects of the fat tax than studies which examine the effects of low-fat eating. Relatively short-term studies of low-fat dieting in a controlled setting (that may have little to do with real life) have generally been found to elicit only modest weight loss. Unfortunately, the effects on weight of longer-term fat restriction are even less impressive: a 2002 review of relevant studies found that the average weight loss in individuals eating a diet lower in fat for 18 months was none at all.
With rates of obesity having trebled in the UK in the last 20 years, it is not surprising that the Government feels compelled to act. However, if the policy-makers in Downing Street are serious about stemming this tide, then it is likely that they will need to invest in a long-term and broad-ranging strategy aimed at supporting individuals in their efforts to eat better and be more active. The evidence suggests that the chances of a tax on fat bringing about a reduction in our collective weight are very slim indeed.
Observer Column – 20th April 2003
Anyone who has an even passing interest in the relationship between diet and health will be aware of the inconsistencies and contradictions that abound in this area. One famous and oft-quoted nutritional anomaly in the so-called French Paradox: while the French eat more than their fair share of fat and tend to run elevated levels of cholesterol in their blood streams, they nonetheless have heart disease rates that are actually supremely low. While a few explanations for this anomaly have been mooted, including the preponderance of red wine in the French diet, why our European neighbours seem to get away with a diet famously rich in foie gras, cheese and red meat remains a mystery.
This week, I thought I’d have a stab at trying to explain the French Paradox, and thought it prudent to look first at the premise on which it is based. Conventional wisdom dictates that the French diet, rich in animal fat and cholesterol, should be at high risk of the artery furring process that is the usual cause of heart disease. This concept dates back to 1953, when a researcher by the name of Ancel Keys published a study of six countries showing that, the more animal fat in a nation’s diet, the greater its rate of deaths due to heart disease. Some subsequent studies have shown similar results, and have been bolstered by evidence that higher levels of cholesterol in the bloodstream do indeed appear to increase heart disease risk.
While such studies have been used to sentence dietary fat and cholesterol to jail, the reality is that they do not prove guilt. The apparent association between a lifestyle-related or biochemical factor and a disease does not necessarily mean that that the factor is the cause of that disease. For instance, car owners have been found to be at statistically greater risk of heart disease. However, common sense dictates that it’s not owning a car per se, but factors associated with this such as lower levels of activity and higher risk of being overweight that are more likely the real problem. In the same way, it is possible that animal fat and cholesterol are not the perpetrators of heart disease, but merely innocent bystanders.
Some support of this concept is to be found in the scientific literature. When Ancel Keys published his first study 40 years ago, other data already existed from other countries that cast serious doubt on the validity of his conclusions. For instance, the deaths due to heart disease in Finland were found to be seven times higher than those in Mexico, despite similar fat intakes. Other studies have shown enormous variance of heart disease rates between regions in countries such as Finland and Italy, despite consistent blood cholesterol levels. In addition, studies designed to assess the effects of lowering cholesterol through dietary means have failed to find consistent benefits. Interestingly, cholesterol-reducing medication known as statins do seem to reduce the risk of heart disease. However, some researchers have suggested that statins exert the benefits not through their cholesterol-reducing effects, but via other biochemical effects they are known to have in the body.
There is considerable evidence that suggests the relationship between animal fat in the diet and heart disease is not as strong or a clear-cut as we have been led to believe. It seems that the real explanation for the French paradox is that it is really no paradox at all.