Are High Protein Diets bad For You?
Are high protein diets bad for you?
We have all heard the claims by now.
- High Protein Diets Damage your Kidneys
- High Protein Diets Deplete your Bones
- High Protein Diets Cause Cancer
- High Protein Diets Cause Weight Gain
- High Protein Diets Damage your Heart
But are these claims about even true?
Let’s debunk the myths once and for all.
Do High Protein Diets Damage Your Kidneys?
According to the research, healthy people can safely consume a high protein diet without concerns about kidney health.
Jose Antonio conducted a one year study on the health effects of high protein diets that supplied 2.51-3.3 grams of protein per kilogram body weight on resistance-trained men age 22-30. He found no evidence that high protein diets reduce kidney health or function.
Antonio completed a later study on resistance trained women and came to similar conclusions that a high protein diet did not reduce kidney health.
Later, Antonio repeated a similar two year study on the effects of a high protein diet on 5 resistance-trained men age 25-35, and again found no evidence that very high protein diets had any negative effect on kidney (or liver) function.
A 2018 meta-analysis found no difference in kidney health between those who consumed higher protein and lower protein diets.
The only group that experienced improved longevity after a reduction in protein was people with end stage renal disease. Unless you have end-term kidney disease, you can probably safely consume high protein diets without any worry about your kidney health.
Do High Protein Diets Deplete your Bones?
No, high protein intakes do not deplete your bones.
One theory states that high protein diets leach calcium from the bones.
But according to this study from the Journal of Bone and Mineral Research, there is no evidence that increasing the acid content of the diet through high protein intakes promotes skeletal bone loss or Osteoporosis.
This study from the National Osteoporosis Society found no difference in bone density between those who consume a lower protein and a higher protein diet.
Other research has actually suggested that higher protein intakes might be protective of bone mineral density, lead to slower bone loss after menopause, and help healing after bone fractures.
Rapuri et. al conducted a study of post-menopausal women and found a positive association between protein intake and bone mineral density. Women in the study with the highest protein intakes had significantly higher total body and spine bone mineral density.
Interestingly, protein supplementation may also benefit those recovering from a hip fracture, and lead to fewer hospitalization days after hip fracture.
Finally, Antonio et. al found no negative effects from a high protein diet on bone health. In fact, his study participants lost no bone mineral density after consuming up to 4.4 grams of protein per kilogram body weight for one to two years.
Do High Protein Diets Cause Cancer?
High protein intakes may be associated with higher rates of cancer, but only when the diet includes certain types of high protein foods.
For instance, high intakes of processed meat and red meat are associated with higher cancer rates. However, high consumption of lean meats, poultry, fish and low fat dairy products are not associated with higher cancer rates.
According to this 2012 study in The Archives of Internal Medicine, red meat consumption was positively associated with cancer, cancer mortality and cardiovascular disease.
However, the researchers of that study estimated that substituting red meat for other high protein food sources such as fish, poultry and low fat dairy could lower cancer rates and mortality.
Moreover, we do not know if the positive association between processed meat and cancer is causal. Even the WHO maintains that processed meat may only increase cancer rates insofar as processed meat increases salt and fat intakes.
It seems that high protein intakes are not associated with higher rates of cancer, as long as a high protein intake is not achieved through high processed meat consumption.
Do High Protein Diets Cause Weight Gain?
High protein diets do not cause weight gain. In fact, high protein consumption can help you lose weight and improve your body composition.
People who eat high protein diets usually experience less hunger overall and subconsciously lower their energy intakes because protein makes your feel more satiate.
High protein intakes make it easier to stick to a reduced calorie diet overall, and they might even contribute to weight loss.
In fact, high protein intakes also help you maintain your muscle mass, even when you have reduced your calorie intake.
High protein intakes up to 2.2 grams per kilogram body weight can help you gain more muscle than at lower intakes. Even if your weight stays constant, more muscle gain can help improve your body composition and lower your total body fat percentage.
In fact, high protein intakes can even help you to limit fat gain even when you consume more calories than you need to maintain your weight.
Antonio et. al. found that at protein intakes up to 4.4 grams per kilogram of body weight, resistance trained athletes gained less body fat during intentional overfeeding periods.
The combined results of all of these studies confirm that high protein diets can assist weight loss, muscle building and retention and even limit fat gain during overfeeding periods.
If you want to improve your body composition while you are dieting, overeating or just maintaining your weight, you should include ample protein in your diet.
Do High Protein Diets Damage Your Heart?
Little evidence exists to suggest that high protein diets damage your heart.
As long as you consume mostly healthy high protein foods like lean meat, poultry, dairy products, and fish as your protein sources, high protein diets may actually benefit heart health.
Higher protein intakes may even benefit patients with heart disease.
For instance, some research even suggests that a high protein diet can reduce cardio metabolic risk, triglyceride levels, visceral fat, cholesterol and blood pressure in patients with heart failure.
Final Thoughts
Hopefully this article provided reassurance that higher protein intakes are safe and do not damage your health. As long as you choose healthy protein sources to include in your diet, eating a high protein diet can be safe and might even have health benefits.
I would love to hear your thoughts on this topic. Please let me know in the comment section below about your experience.
