Eating too much protein is bad for the kidneys
One of the frequently heard criticisms of a high protein diet is that it damages the kidneys. However, there are no studies which show any evidence for this oft repeated fact.
It is true to say that patients with kidney disease or a decline in their renal function, should not follow a high protein diet because, it has been shown, that reducing protein content in the diet appears to lessen the renal function decline. It is easy to see that since not eating a lot of protein is good for people with pre-existing kidney disease then, it may be assumed, a high protein diet is bad for the kidneys. However drawing this conclusion is both illogical and erroneous.
In fact, for patients with renal disease, it is the glycolated proteins, the result of excess sugar in the blood, which cause the problems.
Glycolated proteins are produced when excess sugar in the blood combines with protein molecules producing sugar coated proteins. These sugar coated proteins, known as Advanced Glycolated End Products (AGES), will them combine together to form larger molecules that are too large to pass through the kidneys filtering system. The AGES then reduce kidney function measured by glomerular filtration rate (GFR).
A high protein diet does not produce this effect in healthy kidneys. A recent study involving over 1,600 women revealed that a high protein diet did not affect renal function in women with healthy kidneys. A further study involving men came to the same conclusions.
A third study involving obese volunteers compared high protein and low protein weight loss diets, this study showed that healthy kidneys are able to adapt to the levels of protein consumed and, again, that the high protein levels had no adverse effects on kidney function.
For those individuals with healthy kidneys high protein diets, with reduced carbohydrate intake, will, in fact, control blood sugar levels and therefore reduced the risk of kidney disease developing. It is, however, essential to consult with your medical practitioner before starting any weight loss program.
High protein diets actually make you fat
This is another myth. Eating too much of anything will make anyone fat – the key to weight loss is always the same, eat less, do more. Ingesting more calories than are expended will lead to weight gain – even if those calories come from lettuce leaves. Many calories from protein foods are burned off during the digestive process (the thermic effect of food), protein rich foods are also more satisfying and leave us feeling fuller for longer and, therefore, less likely to snack between meals.
Protein rich foods do not promote the secretion of insulin -this reduces the potential for fat storage. Many carbohydrate foods can cause wild fluctuation in blood sugar levels and insulin production – this increases the likelihood of the consumed food being stored as fat.
Eating too much protein means too much unhealthy saturated fat
Again, this is a myth. It is all a matter of choice – whilst many protein rich foods do contain high levels of unhealthy saturated fat there are plenty of choices which do not. There are a great many foods which contain very little saturated fat and which are perfect for a high protein diet – these include fish, skinless chicken breast, egg whites and legumes