Atkins - A GP's View

Dr Jeremy Sims MB BS MSc MRCGP FRIPH FRSH PGDipHI DipN&H MRNT

There's no getting away from it. The big craze in the slimming world remains the Atkins Diet.

Low-carbohydrate, high-fat equals weight loss according to the Atkins' philosophy. Flying in the face of all medical recommendations for healthy eating. And yes, there are many quick to tell you of their success in following this quirky "regime". Eating what you like (and as much as you like), as long as it hasn't the slightest whiff of starch.

And this summer's hype has been further fuelled, like petrol on the proverbial BBQ (high fat, of course), by two new studies reported in that epitome of medical greatness, the New England Journal of Medicine.

The big questions remain, however. How reliable are these studies? Is the Atkins diet a suitable option to ensure your long-term health? And are there any specific health risks? More on the latter shortly.

Meanwhile. Let's take a closer look at those two studies supporting Atkins. As a discerning consumer of health information, you need to adopt a slight (if not downright overt) scepticism for any new research. That's not to say that you should dismiss every piece of health news with a contemptuous sneer. What it means is that you need to ask yourself some important questions:

1. Is the information reliable? - who produced it and why?
2. Is it unbiased?
3. Is it relevant to me?

So, how do the two studies shape up? To be honest, not brilliantly.

In both studies, middle-aged obese men and women were randomly assigned to consume either a very low-carbohydrate diet (as Atkins advocates), with no calorie restrictions, or a low-fat diet that limited the total amount of calories consumed per day.

In one of the studies, during the first three months, those assigned to the Atkins diet lost an average of 6.8% of their body weight, compared with a 2.7% loss in the low-fat diet group. Similar results were seen after 6 months. But, and this is very important, after 12 months participants in both groups had regained a portion of the weight they had lost, and while the total amount of weight loss was marginally greater in the Atkins group, the difference was no longer statistically significant.

In the other study, which lasted only 6 months, the average amount of weight loss was significantly greater in the low-carbohydrate group than in the low-fat group (12.8 vs. 4.2 pounds). In other words, Atkins may outperform in the very short-term, most probably due to depletion of body glucose stores, water and muscle protein, but it is not a diet to live on for the rest of your life - it has no long-term advantages over other weight loss programmes.

But are these results reliable any way? Not entirely it would seem. Especially when you consider that they are weakened by the high dropout rate (over 40%) and by the fact that some participants adhered poorly to the dietary recommendations.

And now there’s even more bad news for the Atkins aficionados. Despite the apparent, albeit small, benefits of a low-carbohydrate diet for people who have difficulty losing weight, it is not at all without risk. An earlier study has already highlighted the fact that long-term carbohydrate restriction can increase the risk of osteoporosis, with attendant risks of bone fractures, spinal collapse and nerve damage. What-is-more, although in a few studies it has been shown to improve certain cardiac risk factors, a low-carbohydrate diet limits the intake of a wide range of plant-derived chemicals, such as flavonoids, carotenoids, and antioxidants, that may help prevent heart disease, cancer, and other disorders. Rather cancelling out any claimed benefits, wouldn't you say?

These concerns about the health implications are elevated by the latest news that those following the Atkins diet have a far greater risk of developing kidney stones - as much as double the risk. Indeed, evidence shows that since the craze took hold there has been an incredibly sharp rise in the incidence of this disorder, particularly amongst young women, in whom it is usually relatively rare.

Which really does bring us to the bottom line. The evidence for the Atkins diet is still thin.

What can be said is that in the short-term it may indeed aid weight loss. But, let's face it, any fad diet can claim this - especially if you can stick at it without losing motivation. What is far more important is that any changes in your eating habits for weight loss must be agreeable with long-term health, and that the loss in body weight and the subsequent maintenance at a healthier weight are sustainable for life. The growing evidence is that the Atkins diet is unable to support either of these aims.

Therefore, you need to ask yourself, in all honesty, which would I rather be? Crippled by the physical side-effects of the Atkins diet in five, ten, twenty years time, for the sake of a few more pounds weight loss in the short-term. Or slim, vibrant and physically fit in future life - the results you can expect from well-balanced and healthy lifestyle changes - the sort that don't restrict fruit and veg for instance.

The choice is entirely yours. But I know which I would choose.