Meat, Reconsidered

Few foods divide opinion like meat. To some, it's the key to strength and vitality; to others, a cause of disease and environmental harm. Both camps can point to studies that seem to prove their case. As naturopaths, we're interested less in winning the argument than in understanding what the evidence really shows, and helping each person find the balance that nourishes them best.

Meat in the long-lived communities

In the world's "Blue Zones", where people live unusually long and healthy lives, meat isn't absent, but it's eaten sparingly: on average around five times a month, in small portions, often at celebrations, from animals raised outdoors on the family farm. The everyday foods are beans, vegetables, whole grains, nuts and herbs.¹ (Read more in A Natural Age.) Meat played a part in their diets, but a small, high-quality one.

Not all meat is equal

One of the biggest problems with headlines about meat is that they lump very different foods together. The research suggests it matters greatly what kind of meat we mean:

• Processed meat: meat preserved by smoking, curing, salting or adding preservatives such as nitrites. Bacon, ham, sausages, salami, hot dogs, corned beef and most cooked deli meats.
• Unprocessed red meat: fresh beef, lamb, pork, venison and goat.
• Poultry: chicken, turkey and duck.
• Fish and seafood, which have a strong record of benefits for the heart and brain.

Processed meat: the clearest evidence

In 2015, the World Health Organization's cancer agency classified processed meat as a cause of bowel (colorectal) cancer, placing it in the same category of certainty (though not the same level of risk) as tobacco. Eating 50 g of processed meat a day, about two slices of ham or one sausage, was linked with an 18% higher risk of bowel cancer. Red meat was classified as "probably" causing cancer, with less certain evidence.²

It helps to understand what 18% means. It's a relative increase. In the UK, around 6 in every 100 people develop bowel cancer in their lifetime; eating processed meat every day would raise that to around 7 in 100. That's a real but modest effect, and one that's entirely avoidable.

Processed meat is also linked with heart disease and type 2 diabetes. A large review found that each daily 50 g serving of processed meat was linked with a 42% higher risk of heart disease, while unprocessed red meat showed no clear link.³ The salt and preservatives in processed meat may explain much of the difference.

Why might meat cause harm?

• Nitrites and nitrates added to cured meats can form N-nitroso compounds in the gut, which can damage the cells lining the bowel.
• Haem iron, the form of iron in red meat, is well absorbed, but in large amounts it may also encourage the formation of these compounds.
• High-temperature cooking, such as barbecuing, grilling and frying until charred, creates heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs), which can damage DNA. It also creates advanced glycation end products (AGEs), which encourage inflammation and oxidative stress.⁵ (See The Quiet Fire.)
• The gut connection. Gut bacteria turn carnitine and choline from red meat into a compound called TMAO, which has been linked with hardening of the arteries.⁶ Interestingly, people who eat mostly plants produce much less TMAO, even after eating meat, because their gut bacteria are different. (See The Master Regulator.)

The sulphur question: acid load, the gut and inflammation

Meat, fish, eggs and cheese are rich in the sulphur-containing amino acids methionine and cysteine. When the body breaks these down, they form sulphuric acid, which adds to what's known as the diet's acid load. Vegetables and fruit work the other way: their potassium and organic acids, such as citrate, leave alkaline residues behind. A diet heavy in meat and light on plants asks the body to clear more acid, every single day.⁷

The body is remarkably good at this. The lungs and kidneys hold the blood's pH within a narrow range, so food doesn't make the blood itself "acidic". But keeping that balance comes at a cost, and a steady, high acid load appears to wear on the body over time:

• The kidneys do most of the work of clearing acid. In large studies, a higher dietary acid load is linked with a faster decline in kidney function,⁸ and in trials with people whose kidneys were already weakened, adding fruit and vegetables protected kidney function as well as bicarbonate medicine did.⁹ A high intake of animal protein also makes kidney stones more likely: it raises calcium and uric acid in the urine and lowers citrate, which normally helps to prevent stones.
• Muscle. To help buffer acid, the body draws on muscle protein. In older adults, diets rich in potassium-containing fruit and vegetables are linked with better-preserved muscle.¹⁰
• The gut lining. Sulphur from meat, together with the sulphite preservatives in some processed meats, feeds gut bacteria that produce hydrogen sulphide. In small amounts this gas is a normal messenger; in excess it can thin the protective mucus that lines the bowel and fuel inflammation. In a study of people with ulcerative colitis, those who ate the most meat, especially red and processed meat, were around three times as likely to have a flare-up during the following year.¹¹ A diet high in animal protein has also been linked with a greater risk of developing inflammatory bowel disease in the first place.¹²
• Asthma. In a French study following nearly 1,000 adults, those who ate cured meats four or more times a week were more likely to find their asthma symptoms worsening over time.¹³ Sulphites, used to preserve some sausages, burgers and other processed foods, can also trigger wheezing: an estimated 3 to 10% of people with asthma are sensitive to them.¹⁴
• The skin. Sulphites can cause hives and skin flares in sensitive people. Research on meat and eczema itself is still limited, but a global study of children and teenagers linked eating fast food three or more times a week, often built around processed meat, with more severe eczema and asthma.¹⁵ Triggers vary greatly from person to person, which is why it's worth exploring them with a practitioner rather than cutting out whole food groups alone. (See Skin Deep.)
• Gout. Red meat, and organ meats in particular, are rich in purines, which the body turns into uric acid. Higher meat intake is linked with a greater risk of gout.¹⁶
• Growth signals. Large amounts of animal protein raise IGF-1 and switch on mTOR, the growth pathway described in A Natural Age. In middle age, very high-protein diets based on animal foods have been linked with higher rates of cancer and earlier death. After about 65 the picture changes, and more protein helps to protect muscle.¹⁷

One old idea hasn't stood up: that this acid draws calcium out of the bones. Large reviews have found no such harm, and good protein supports strong bones when calcium intake is adequate.¹⁸ (Read more in Living Bones.)

Plants are the natural counterweight. The same portion of meat can leave a heavy or a light load depending on what sits beside it: served with plenty of vegetables, leafy greens and herbs, it leaves the body far less to clear. It's one more reason the traditional diets that included meat were always so rich in plants.

Less meat, but better meat, alongside plenty of plants.

What meat offers

Meat is also a highly nourishing food, and for some people it's especially valuable. It provides:

• Complete protein, with all the essential amino acids in the right balance for building and repairing muscle.
• Vitamin B12, which is found almost only in animal foods and is essential for energy, the nerves and red blood cells.
• Haem iron, which is absorbed far more easily than iron from plants.
• Zinc, selenium and choline, and, in liver, vitamin A in its ready-to-use form.

Good-quality meat can be particularly helpful for women with heavy periods who struggle with low iron, for older adults trying to protect their muscle strength, for people recovering from illness, and for growing teenagers. (Read more in You Are What You Absorb.)

Quality matters

• Grass-fed and pasture-raised. Meat from animals raised on grass contains more omega-3 fats, conjugated linoleic acid (CLA) and antioxidants than meat from grain-fed animals.¹⁹
• Organic. A large review found organic meat contains around 47% more omega-3 fats than conventional meat.²⁰ Organic farming also limits the routine use of antibiotics, which is contributing to the global problem of antibiotic resistance. (Read more in Why Eat Organic?)
• Animal welfare. Animals raised outdoors, able to behave naturally, live better lives. Look for labels such as Pasture for Life, Soil Association organic or RSPCA Assured.
• The planet. Beef and lamb have by far the largest environmental footprint of any food, using more land and producing more greenhouse gases than any plant food.²¹ Eating less, and choosing meat from farms that care for the soil, makes a real difference.

Nose to tail

Our ancestors ate the whole animal, not just the prime cuts. Slow-cooked cheaper cuts, such as shin, shoulder and cheek, are tender, flavourful and affordable. Liver is one of the most nutrient-dense foods in the world, rich in vitamin A, B12, iron and folate. Bones make a nourishing broth full of gelatin and minerals (see our Healing Bone Broth). Eating this way honours the animal and makes higher-quality meat affordable. (See Closing the Divide.)

How much is enough?

• The NHS advises that people who eat more than 90 g of red and processed meat a day cut down to 70 g or less.
• The World Cancer Research Fund recommends no more than three portions of red meat a week (about 350–500 g cooked weight) and very little, if any, processed meat.
• The EAT-Lancet Commission, which designed a diet for both human health and the planet, suggests around 100 g of red meat a week, alongside poultry, fish, eggs and plenty of plant protein.²³

A simple way to put this into practice is to think of meat as a flavouring or a side rather than the centre of the plate, and to make most meals plant-based.

Meat and your constitution

In traditional Chinese and Ayurvedic medicine, meat is seen as warming, heavy and building. It may be strengthening for someone who is cold, thin, pale and depleted, but too heating and heavy for someone who already runs hot, feels sluggish or tends towards inflammation. A good broth or slow-cooked stew is often recommended for people recovering from illness. (Read more in The Architecture of Balance.)

Thriving on plant protein

Many people are healthy on a vegetarian or plant-based diet. Beans, lentils, chickpeas, tofu, tempeh, quinoa, nuts and seeds all provide plenty of protein, and there's no need to combine them carefully at each meal, as long as you eat a variety through the day. If you eat little or no meat, pay particular attention to:

• Vitamin B12, which a fully plant-based diet can't provide. A B12 supplement or fortified foods are essential.
• Iron, from pulses, dark leafy greens, seeds and dried fruit, eaten with vitamin C to help absorption.
• Iodine, zinc and omega-3 fats, from seaweed, seeds, nuts and algae oil.

Our Recipes include dozens of plant-based meals rich in protein, from Classic Tarka Dal to Plant-based Cassoulet.

At Rootwise, our approach to meat is simple: less and better, alongside an abundance of plants. Some people thrive on a little good-quality meat; others feel best without it. A Rootwise consultation can help you find the balance that suits your body, your values and your health.