Posts Tagged ‘low carb’

are high protein diets safe?

June 2, 2010 1 comment

Diets high in protein have been the staple for many athletes and bodybuilders over the years.  Protein is the essential building block for muscles and increases size, strength and power. A very good thing for athletes and anyone who exercises regularly.  But can we have too much of a good thing?  That seems to be a common belief among people who argue that high protein diets can cause health problems like kidney dysfunction and osteoporosis.

Let’s take a look at what actual research has been done on high protein diets to clear up some of the myths about associated health problems.

There is no evidence linking high protein diets to kidney problems in healthy people

No studies have shown that high protein consumption can cause kidney dysfunction in healthy people.  As Dr John Berardi notes, “there is absolutely no data in healthy adults suggesting that a high protein intake causes the onset of renal (kidney) dysfunction. There aren’t even any correlational studies showing this effect in healthy people.” The only research that shows a correlation between high protein intake and kidney problems is in people who are already suffering from kidney disease.  So for those who have kidney disease, a high protein diet may not be advisable.  But there is no reason to believe that this is the case in healthy people.

Studies actually show health benefits from high protein diets

Bone health:  some people believe that high protein can cause a loss of calcium and lead to problems like osteoporosis.  But when studies were done to test this belief, they actually found the opposite to be true, with a “positive association between protein intake and bone mineral density”.

Blood pressure: large studies in the US [1, 2] and China [3] have found a negative relationship between blood pressure and the amount of protein consumed – indicating that high protein diets are associated with low blood pressure.

Heart disease: a 14 year study of over 80,000 women found “that replacing carbohydrates with protein may be associated with a lower risk of ischemic heart disease”.  This is truer in cases where protein comes from lean sources like chicken, fish and vegetables, and less so in cases where protein comes from high cholesterol and saturated fat sources (pork, beef, lamb, eggs, etc.).

Liver function: protein in needed for liver tissue repair and high protein diets have been found to be beneficial for people suffering from liver disease.

We are genetically designed to consume high protein diets

As mentioned in my previous blog about the caveman diet, proponents argue that developments in food have far outpaced human genes.  We are built to eat unprocessed foods, like fruits, vegetables, nuts and lean meats. Palaeolithic diets were high in protein – around 3 to 4 times more protein that in modern diets.  Arguing in favour of the cavemen diet, Dr Anssi Manninen from University of Oulu in Finland states, “it is implausible that an animal that adapted to a high protein diet for 5 million years suddenly in 10,000 years becomes a predominant carbohydrate burner.”