Just how unhealthy is it to eat meat?

Depends on the meat

Diet & Fitness

22nd October 2015

We’ve become rather used to categorising foods as good or bad. It’s simpler that way. Some foods are easy — sugar is the most recent pantomime villain (boo!) while kale and coconut water are the latest heroes (hurrah!) — but what happened to red meat, which used to be a baddy, is it still worthy of a big boooo?

The vilification of red meat began in earnest in the 1960s following landmark postwar research entitled the Seven Countries Study, which established a link between meat consumption and cardiovascular disease. It was believed that saturated fat raised cholesterol levels, in turn increasing the incidence of coronary heart disease, and as red meat (along with butter and eggs) is a common sources of saturated fat, it was directly implicated. More recently, we have understood that saturated fat intake alone is unlikely to raise cholesterol compared to that of sugars and carbohydrates — but does that mean meat is off the hook?

Historically, many of the dietary studies have researched the outcome of eating ‘meat’, a term that encompasses red and processed meat. The resulting reports included increased incidence of colorectal cancer as well as heart disease — and so challenging this strong belief has been a task. But processed meats are quite different from the fresh variety as they contain sodium nitrate, a preservative that is converted into a nitrite on contact with saliva or enzymes in the digestive system. Nitrites can then be further converted into nitric oxide or nitrosamine, the former being beneficial, the latter less so. Nitrosamines are created when nitrites are combined with amino acids (present in protein) and heat. In other words, fresh meat when cooked and preserved increases numbers of nitrosamines, which have been linked to colorectal cancer.

Concentrating on fresh unprocessed red meat (beef, lamb etc), there are distinct nutritional benefits on offer in the form of iron, together with zinc and the B group of vitamins including B12. But the concentration of nutrients is somewhat dependent on the type of feed used in rearing the animal. Some herds are fed with corn to bulk them up while others graze naturally on grass. Meat derived from grass-fed animals is generally nutritionally superior in terms of essential fats as it offers over four times the amount of omega 3 than grain-fed. Omega 3 is noted for its anti-inflammatory potential while omega 6, the prevailing fat in grain-fed meat, can encourage inflammation. Grass-fed also tends to be higher in iron, zinc, vitamin E and beta-carotene and is a worthy source of protein.

How the meat is cooked is a factor, too. Exposing fresh red meat to direct flames or allowing it to burn produces heterocyclic aromatic amines and polycyclicaromatic hydrocarbons. These increase the incidence of some forms of cancer and so overbarbecuing even the finest organic grass-fed red meat from a herd raised by nuns, massaged by professionals and certified kosher by the Chief Rabbi will turn it into the nutritional equivalent of a slice of iffy ham from some discount value range.

Although eating processed meat carries more of a risk than red meat, does that make the latter ‘safe’? A meta-analysis of studies published in the British Journal of Nutrition last year considered data from 13 studies involving over 1.6 million individuals. This concluded that those eating the most processed meat had a 22 per cent increase in mortality from any cause and 18 per cent increase from cardiovascular disease. Even small amounts of processed meat might carry risk, as eating an extra 50g a day showed a positive association with mortality rates, while eating an extra 100g of red meat showed only a weak positive, but nonetheless a positive. Bear in mind that eating x means we don’t eat y, and so eating large amounts of processed or red meat means that we are likely to eat fewer vegetables and so less fibre, fewer antioxidants etc and to some extent this will affect the outcome.

In short, processed meat intake carries increased risk of mortality, cancer and cardiovascular disease while red meat intake showed a slight increase in risk. Where does this leave us? All things considered, I think that processed meats should be a rare occurrence. A slice of ham or bacon here and there when added to a decent diet shouldn’t result in ending up on an NHS waiting list. Nor should 200/250g of red meat twice a week as long as it is cooked carefully and not burnt. Ideally, the red meat would be grass-fed but that can cost anything from 25 per cent upwards more. (Grain-fed is still a decent enough choice).

To my mind, the joy of eating a rib-eye steak, medium rare, with some fiery horseradish sauce once a week is a pleasure, which means that red meat, enjoyed sparingly, is a nutritional hero. Hurrah.

  • Tamerlane

    No more health stories! Ban all health stories for ever and ever. Amen.

  • PMC

    Yeah, so what is the actual risk, rather than the increased risk? If you want to know, go here http://www.cdc.gov/cancer/colorectal/statistics/age.htm and multiply the number by 1.18 to give you your risk factor. Mine is about 0.3% rising to 2.5% over the next 30 years. Therefore, nothing to see. Can we start applying some rigour to science reporting please? I’ve had several conversations with people today who are convinced that eating bacon means they have almost a 1 in 5 chance of developing bowel cancer.

    • Quentin Vole

      Because that’s what they want you to hear when they talk of an 18% increased risk, when in reality it’s at most a couple of %age points (even if you swallow all this guff).

      But let’s assume that this “study of studies” (science-speak for a bunch of post-grad students ploughing through the literature with a calculator in hand) is actually meaningful and that there’s a genuine connection between intake of processed meat and colo-rectal cancer. The obvious question that raises is: what is it in processed meat that causes cancer? Is it present in Serrano jamon (just salt and air-cured pork leg), or is it all the nitrites and other E-numbers present in the cheapest supermarket pack of ‘bacon’?

      • PMC

        How long before there’s a campaign for a Bacon Tax?

  • Malcolm Stevas

    We’re supposed to have postgrad-level science skills before we eat meat, it seems. Correct me if I’m wrong, but humanity has been eating (and processing) meat since the dawn of Homo sapiens. I think I’ll carry on with the steak, the bacon sarnies, the chorizo, etc.
    This kind of thing only encourages the faddists and the health fascists in their shrill denunciations.

  • commenteer

    I note that the red meat should be ‘not burnt’. As I understand it, the research around burnt food was done entirely on rodents. Humans were eating meat charred on the bonfire throughout the evolution of modern man, and I am sceptical, unless you can show me otherwise, about the veracity of this claim.

  • frank davidson

    Oh dear. Shall I starve then?

  • Sir Bogsworth Witchfield

    I think behind this declaration, lies an agenda. Pushed by those who’d rather eat cucumber for breakfast, and dine on broccoli for supper! And I say to them : Get your fill. In the mean time I’ll eat the lamb and the beef steak too!

  • Observer1951

    These scare stories always suffer from a lack of any real scientific perspective. For example to say nitrosomes are carcinogenic without any mention of the systemic exposure to the nitrosamines is nonsense. Any toxicologist would tell you that. Carcinogenicity is related to systemic exposure and exposure time, not to mention genetics.

  • goodsoldier

    Soon enough there will be war and we will be rationed and then remember how we resisted the red meat and bacon and sweet tea. The propaganda on every issue is getting stronger every day. We are being adapted to take orders.

  • My take is: 1. Never trust any dietary or nutrition ‘science’ from the 1960s — especially if it was American (naturalized citizen here: makes no difference: they were grinding axes that make the climate change scam look like playtime).

    2. Anyone that criticizes ‘fast food’ and esp. McDonalds’ in the 21st century is living on fumes — as the guy that wrote a book on habits that I’m reading sure does. Contrary to his claim, no one has to buy ‘sugary’ pop: it comes in ‘diet’ and has for donkey’s years now (that means: no sugar). No has to buy ‘salty fries’: you don’t have to choose fries at all, and far from being salty, I always find them undersalted (on the occasions when I treat myself, usually on a long out-of-state drive) and have to add some. Also, they are not ‘engineered’ to ‘disintegrate’ on contact with your tongue: they are COOKED, like any other food. Gee whiz. Finally, NO ONE has to buy battered chicken bits or hamburgers if they don’t want them: ALL the fast food chains provide a wide variety of other foods, including quite high-quality salads. Yes, salads, you know, with lettuce and lots of other veg. Chick-Fil-A is my fave of restaurants of this kind: inexpensive, high-quality food-to-go that people in the past would have considered a world-class wonder. Instead our fatuous nanny-staters and bien-pensant know-nothings sneer. I’m calling them out as ignorant, bigoted, unscientific and WRONG.

    3. There is nothing wrong with *any* food as long as it is made and cooked with an eye to simplicity and quality. Meatloaf: prime example. You could make a disgusting meatloaf if you’re the sort that thinks Twinkies make a great treat. But meatloaf can be just as wholesome as anything else that is not caught fresh from the sea. In short, a lot of the problem here is that some people have no discernment whatsoever and will eat the most goshawful cr*p, but they also sport innumerable tattoos and watch TV because they have nothing better to do. We should not condemn whole food groups or macronutrients because such ghastly people exist (in the millions and millions, gawd help us).

  • Sheena