What is the truth about the role of meat in a healthy diet?
There is so much conflicting information out there on whether or not you should eat meat as part of a healthy diet. For many it is an emotive subject, either one way or the other. There is a whole spectrum of opinion - from people who love a good barbecue or Sunday roast and can't imagine life without meat, to those for whom eating the flesh of an animal is totally abhorrent for ethical, environmental, religious or other reasons.
But what is the actual evidence for a healthy diet - meat or no meat?
Early peoples ate meat
It is true that we as humans are adapted to eat both meat and plants. Early humans would hunt for mammals, birds and fish and eat them. However they did not have ready access to these as we now do via the supermarket shelves and local butcher. Meat procurement would have been a physically demanding task and one that was not achieved every day by any means. When meat was available it had to be eaten- fast. Lack of refrigeration meant that it would have gone off quickly, especially in warmer climates. On non- successful hunting days the diet was made up of plants- roots, leaves, berries, tubers.
Meat in the modern diet
The modern diet is so very different. Not only do we have easy access to meat, requiring no physical effort whatsoever, but we also have domesticated and bred it so it is no longer the lean, muscular flesh of wild animals. We process it: smoking; adding additives to change the flavour or to preserve the meat longer; salting or mixing it with other ingredients (eg in sausages).
The benefits of meat eating
There is no doubt that meat contains nutrients which are essential for good health. Meat (including poultry) are great sources of protein. It also provides other nutrients your body needs such as iodine, iron, zinc, vitamins (especially B12) and essential fatty acids. Iron is a key nutrient and one that young women in particular can struggle to maintain enough of. Red meat is an easy way to get plenty of iron and iron from animal sources is more easily absorbed by the body than iron from plant sources.
Despite all this, it is absolutely possible to obtain enough protein from a pescatarian (plants and fish/seafood), vegetarian (plants plus eggs and dairy products) or vegan diet (plants only, no foods of animal origin whatsoever).
The downsides
Vitamin B12 is often problematic in a vegan diet and a quality B12 supplement should be taken to avoid neurological damage.
Iron can be challenging especially for those who are pregnant, breastfeeding, menstruating or who have a heavy physical workload such as athletes. In these cases attention should be paid to including plant foods rich in iron and in some circumstances an iron supplement may be necessary, though not all the time.
Iron overload can be as harmful as iron deficiency anaemia so you should get a blood test before embarking on supplementation, and then retest after a couple of months to see how your iron levels have changed.
In terms of evidence-based healthy diet advice, the consensus of evidence shows that diets which contain more plant foods and very little or no meat do lead to better health outcomes. Whether this is to do with eating less saturated fat, less salt (especially in processed meats) or simply the fact that more meat on the plate leaves less room for plant foods such as vegetables, fruits, nuts, seeds and whole grains is unclear. Probably it's a combination of all of them.
Links to Chronic Disease
Diets high in meat and processed meats have been linked to a higher risk of colorectal (bowel) cancer. A diet that is most protective against bowel cancer is one high in fibre. Animal foods contain no fibre at all, thus the less meat on your plate, the more room there is for fibre-rich plant foods.
Processed meats are high in salt and high salt diets lead to high blood pressure, a key risk factor for stroke.
Oddly, diet containing more meat (versus low meat diets) have a greater risk for type II diabetes. This may seem counterintuitive as diabetes has traditionally been 'all about carbohydrates'. Perhaps it is also about consumption- higher meat might mean eating larger portion sizes overall?
Obesity is known to be a key risk factor for type II diabetes.
In all of these chronic conditions inflammation is an underlying cause and good gut health is protective against inflammation. A wide variety of plant foods is known to create a healthy population of microorganisms in the gut and so perhaps it is that 'crowding out' of plants foods when meat is the main ingredient on the plate that has led to this trend. What we do understand more fully now is that the whole diet pattern is the key to good health, not one food or food group.
Environmental Concerns
The health of our environment going forward is another factor to consider. Animal production for meat is a huge source of greenhouse gases and a major reason for land clearing. Beef production has the biggest impact with chicken and pork being somewhat better. Dairy foods also have a high environmental impact.
Balancing your plate and your whole diet
Although I choose not to eat meat, there is no need to give it up entirely. What is needed, worldwide, is a more balanced approach to eating. The days of enormous steaks are outdated. A portion the size of the palm of your hand is enough to provide all your protein needs in a meal. That leaves the rest of the plate ready to fill up with leafy greens, brightly coloured vegetables and whole grains or high fibre starchy vegetables. Don't forget herbs and spices, nuts and seeds to make the whole thing more delicious and varied in plant foods.
Processed Meats
The evidence for processed meats being a class one carcinogen is pretty convincing. As far as you can (and I know that giving up bacon is challenging for some!) avoid processed meats. The processes used (especially nitrates used in curing) and the high salt content are definitely not good for you. Keep them for very occasional use if at all.
The Compromise
We have shown that meat is a great source of protein and other nutrients, some of which would be deficient if we ate no animal products at all. However, there are risks attached to a high meat diet, and it is not environmentally sustainable.
To create a healthier gut microbiome and to decrease your reliance on meat in the diet:
make an effort to swap fish for meat twice a week if possible for its anti-inflammatory omega three containing fats. Fish is expensive but cheaper tinned fish or cheaper types such as Hoki are still highly nutritious.
Make plant proteins such as beans, peas, lentils or tofu the main event. Other cultures have long embraced these cheap protein sources and have created some delicious recipes- think vegetarian Mexican bean tacos, Indian vegetarian curries, Japanese stir fries and soups with tofu as a start.
Decrease the amount of meat on the plate and fill up with vegetables and wholegrains.
Practice "meat free Monday" (or Tuesday or Wednesday...)
Buy meat from local sources where possible so you know what it ate and how it was processed (preferably not at all- just cut up!) .
Ditch or minimise processed meats.
Consider how many meals you have that contain meat- maybe if your dinner is meat based you could have a vegetable based lunch?
Meat can be a useful source of nutrients in a healthy diet and doesn't necessarily have to be abandoned in order attain good health. Follow the guidelines above to eat meat in a more sustainable and moderate way and you can enjoy your meals as well as good health!
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