Today’s media reports again highlight a potential link between eating lots of red meat and cardiovascular disease (CVD).  This time, the culprit is allegedly a small molecule called carnitine, which is naturally present in red meat but are we getting the full story here?  Read on to find out…

 

Red meat itself has been linked to cardiovascular disease owing to its saturated fat content for many years, leading to recommendations to limit intake to 70g a day or around 2 portions a week.  Recently, the link between saturated fat and CVD has been questioned, with diets high in refined sugars, processed meat and trans fats being more closely linked to disease risk.  The benefits of red meat consumption such as the source of iron for energy levels and zinc for the immune system would support a moderate intake, such as those recommended so I would never advise total avoidance.

 

Carnitine is naturally present in red meat and animal products like milk and dairy foods.  It has now being linked to cardiovascular disease because a piece of research (in mice) has shown that the bacteria in the gut break it down into a product called TMAO, which may cause atherosclerosis (furring up and potential blockage of arteries).  People with high levels of carnitine in the blood seem to have more risk of cardiovascular disease.  Those with high levels of carnitine in the blood also seem to have a different balance of gut bacteria, with more bacteria present that create this TMAO from carnitine.  It would therefore seem that those with a high carnitine intake, from food or supplements, would be at higher risk of cardiovascular disease.  However, read on to see a closer examination of the science…

 

The science that associates diets and blood test results with disease risk is a tricky business.  Those with diets high in red meat tend also to be smokers, take less exercise, eat more processed and refined carbs and eat fewer fruit and vegetables.  Any one of these factors could increase cardiovascular risk.  Those with these type of unhealthy lifestyles are likely to have a different profile of gut bacteria so when they consume foods containing carnitine, they are more likely to produce this TMAO.  This is borne out in the research which shows that even when vegetarians consume lots of carnitine, they DON’T product lots of TMAO.  It therefore seems to be more about lifestyle overall and its impact on gut bacteria than carnitine consumption itself.  Eating minimally processed foods, plenty of fruit and vegetables and moderate amounts of red meat to maintain a healthy gut with the right ‘friendly bacteria’ is the best approach.

 

Let’s not forget, humans have consumed red meat in large quantities for many thousands of years but have only been eating refined carbohydrates and processed foods for a few hundred years at most.

 

It’s the overall diet and lifestyle that are important, not least because this helps to maintain healthy gut bacteria and reduce cardiovascular risk.  Regular exercise and a healthy balanced diet, incorporating plenty of fruit and vegetables and limiting highly processed foods is the best way to reduce risk of disease.  Those with unhealthy lifestyles who use carnitine supplements for the purpose of fat burning should first address their diet and exercise levels before popping the pills.

Leave a Reply

Your email address will not be published. Required fields are marked *