The latest news from German slaughterhouses have certainly given the vegetarians and vegans community a new boost. In addition to animal welfare and ecological aspects, avoiding meat is usually also based on the desire for a healthy diet. What does science say

1. Consensus: little meat is okay, but not really necessary

Every German eats 150 grams of meat and meat products on average every day. That doesn’t sound like a lot, but it clearly exceeds the maximum 600 grams that the German Nutrition Society per week finds acceptable. Many consumers are also significantly higher. It is these “meat eaters” who are mentioned in the studies on the harmful effects of meat consumption.

But even with those who eat a lot of meat, there are differences: because those who eat a lot of unprocessed meat, and at the same time high in fiber and low in sugar, have a low risk of disease. This is the case, for example, with the Paleo diet.

Experts consider the Mediterranean diet to be the best nutritional method in the world, and it has been for two decades. In 2019 she was once again named the best diet of the year by “US News” . A lot of vegetables, fish and olive oil end up on the plate, but little meat and processed foods.

In comparative studies, it is not vegetarians and vegans who do well, but people who eat little meat.

But you can also say with a clear conscience to Tilmann Kühn, nutritional epidemiologist at the German Cancer Research Center (DKFZ) in Heidelberg: “If you eat wholesome vegetarian food, your body is fine. On the contrary, according to scientific findings, a vegetarian diet is actually very healthy. ”With one small caveat:“ Less meat ”only makes sense if the calorie advantage is not topped up with pizza, biscuits or meat imitations.

2. Those who do not eat meat also live more healthily in other ways

Numerous studies have shown that the biggest meat fans usually do not have good eating habits. Even if you neglect the nutritional value of individual foods, a diet high in meat and sausage as well as sugar, white flour and saturated fats from ready-made foods is unhealthy. Because healthy foods such as vegetables, fruit, legumes, whole grains or nuts are definitely neglected.

3. meat or plant? Nutritional studies are conditionally meaningful

In the laboratory, it is possible to determine how certain nutrients affect human cells. Studies with humans don’t work like that. The health comparison “meat eaters versus vegetarians” is only possible in observational studies. Their conclusions are only an approximation of reality. Too many factors play a role in health for the question to be reduced to schnitzel and tofu . For example: is a chain-smoking vegan healthier than an athletic meat eater?

Epidemiological studies can never conclusively prove that meat consumption is unhealthy. And it is also not conclusively clear which individual ingredients are harmful to health.

4. When it comes to meat, it depends on the color

Beef, pork, lamb or sheep provide the so-called red meat. It is said to cause cardiovascular diseases and problems with the blood vessels.

For US researcher Stanley Hazen from the Cleveland Clinic, a metabolic product of the carnitine contained in red meat is responsible for this. To prove this, he had 113 test subjects eat 250 grams of steak a day for four weeks. A two-week break was followed by four weeks with a correspondingly large amount of (white) poultry meat and, at the end, a meat-free month.

The result , published in the “European Heart Journal”, showed a significant 3-fold increase in the TMAO plasma concentration during the steak weeks. TMAO is produced during the metabolism of carnitine and is a risk marker for hardening of the arteries in the blood vessels. The diet with poultry and vegetables led to a decrease in plasma concentrations in the test subjects.

Red meat is also directly or indirectly involved in the development of cancer.

For example, studies by the DKFZ have shown that people who eat a lot of red meat have increased biomarkers of certain roasting substances, such as those produced during roasting and grilling, swim in the blood. These people were at an increased risk of developing colon cancer.

In the large-scale EPIC study across Europe, 519,000 test persons were examined to find out the connection between diet and cancer .

The results show that red meat can increase the risk of colon cancer. Accordingly, the risk of the disease increases by almost 50 percent if the daily consumption of meat is 100 grams above the recommended amount. The same amount of sausage products increases the risk by as much as 70 percent.

The risk of stomach cancer is also said to be related to heavy meat consumption. In people infected with the Helicobacter pylori bacterium, the risk increases by a factor of five.

5. Theory 1: Iron makes meat unhealthy

There are various theories about why red meat is so problematic. The so-called iron load hypothesis is based on the fact that red meat contains a comparatively high amount of iron. This so-called heme iron has a high bioavailability, unlike iron from plant food, and thus enters the organism in larger quantities.

It has long been suggested that high levels of iron in the blood increase the risk of cancer . However, this theory has not yet been proven by studies.

6. Theory 2: BMMF make meat unhealthy

Scientists working with Nobel laureate Harald zur Hausen believe they have found another cause: a previously unknown class of pathogens is responsible for the increased risk of colon cancer .

These “Bovine Milk and Meat Factors (BMMF)” enter the human intestines through the consumption of meat and dairy products from European cattle. There it comes to a chronic inflammation, which indirectly promotes the development of colon cancer.

7. Avoiding meat protects the intestines

Vegetarian foods contain fiber, which has a positive effect on the microbiome in the gut. Vegans have a particularly large number of them. In addition to fruit and vegetables, lactic acid foods such as yogurt also support the intestinal flora. Vegetarians often consume these. Researchers from the University of New York have confirmed that vegans and vegetarians have more protective types of gut bacteria than meat eaters.

Meat also poses a cancer risk through its preparation and processing: for example, when meat is heated up, several potentially harmful substances are formed at the same time, including so-called polycyclic aromatic hydrocarbons (PAHs); curing also produces nitrosamines. These substances can promote the development of cancer, and above all they increase the risk of colon cancer. Methods such as curing and intense heating are particularly used for industrially processed meat, such as sausage and ham. Accordingly, processed meat products are particularly unhealthy.

8. Avoiding meat makes you slim

Researchers at the Max Planck Institute for Cognitive and Neurosciences (MPI CBS) and the Leipzig University Hospital examined almost 9,000 people, what connections there are between body and mind on the one hand and not consuming animal products on the other. regardless of age, gender and level of education. The study was published in June 2020 in the specialist magazine “Nutrients”.

The result of the physical impact: the less food of animal origin was on the menu, the lower the average body mass index (BMI) and thus the body weight. “Products that are excessively high in fat and sugar make you fat. They stimulate the appetite and delay the feeling of satiety. If you do without animal foods, you eat fewer such products on average, ”explains Evelyn Medawar, first author of the work.

9. Avoiding meat and the psyche

With regard to the psychological effects of the meatless diet, the Leipzig study found no particular susceptibility to neuroses in vegetarians. The study director Veronica Witte says: “Previous analyzes had found that more neurotic people generally leave out certain food groups more often. We focused solely on avoiding animal products and could not observe any correlation. ”No connection was found between a predominantly plant-based diet and depressive moods. There was evidence of this in previous studies.

However, the researchers found a difference in one of the determining factors of personality: the extroversion or introversion. People with predominantly plant-based foods on the menu are more introverted than those who eat primarily animal products. The study authors have not yet found an explanation for this.

The trace element iron is indispensable for a number of vital metabolic functions in the body. As a component of hemoglobin in the red blood cells, it supplies every body cell with oxygen. Iron deficiency, which manifests itself in anemia, exhaustion, susceptibility to infection, affects around 20 percent of women and ten percent of men in Germany. The higher risk for women is explained by menstruation and decreases accordingly when the childbearing phase of life is over.

Many people have an excess of iron – and know nothing about it

Iron deficiency is known and many nutrition-conscious people pay attention to adequate iron intake. However, significantly more people could have anything but an iron deficiency, namely too much of this trace element. Probably very few people know about it, although it carries a high risk of disease.

Heme iron and non-heme iron: these are the differences

First and foremost, it is important for these relationships – there are the two known, different forms of iron, only one of which can be hazardous to health:

1. Heme iron , i.e. bivalent iron (Fe), mainly found in red meat and sausage. Heme iron has a high bioavailability, the body can use at least 20 percent from food.

2. Non-heme iron , trivalent iron (Fe3), from plant-based nutrient suppliers such as legumes, whole grains, nuts, oil seeds and various types of vegetables. Non-heme iron must first be oxidized to some form of Fe in the small intestine in order for the body to use it. In this way, only around five percent of the iron from food comes into play.

The iron requirement per day is 15 milligrams for women and 10 milligrams for men.

Underestimated health risk heme iron

What is certain is that most people in industrialized nations have at least a sufficient supply of the trace element. Due to our meat and sausage-heavy diet, a large part is even oversupplied with heme iron, and thus risks diseases. Various studies indicate these relationships .

“We assume that too much heme iron can have negative health consequences through eating meat,” explains Matthias Riedl, board member of the Association of German Nutritionists (BDEM) and diabetologist, nutritionist, internist, managing director and medical director at Medicum Hamburg.

The human organism is not prepared for high meat consumption

Normally, a complex mechanism of substances in the liver and intestines controls the iron level. If too much iron storage protein ferritin is measured, the body slows down absorption. “This does not work adequately with large amounts of heme iron, the body continues to absorb it, simply because this form of iron is extremely easy to use,” says the expert.

The nutritionist explains that the cause lies in our evolutionary history. Up until two million years ago, humans were purely plant-eaters, only then did they add animal consumption. That was sometimes more, mostly less meat – definitely a lot less than is regularly eaten today. The human organism is not prepared for this.

High consumption of heme iron feeds cancer cells

The excess iron is then deposited in the pancreas, liver and spleen, which can put stress on the organs. But that’s not all. “Heme iron can promote mutations via certain chemical compounds – for example in intestinal cells, but also in other cells,” warns the internist.

In addition, these compounds have a cytotoxic effect, so they can not only change cells, but also damage them. “And cancer cells, on the other hand, are properly fed by heme iron, so to speak,” says the expert. Malignant cells have a high demand for this trace element. A high consumption of heme iron means that existing cancer cells grow better and are stronger against the immune system.

Meat lovers are more likely to develop diabetes and arteriosclerosis

In addition to the connection between heme iron and cancer, many nutritional studies have shown two other negative effects of the “meat iron”:

1. Numerous studies show that people who consume a lot of sausage and meat are particularly likely to have type 2 diabetes .

2. In addition, this dietary preference often leads to arteriosclerosis , with the well-known secondary diseases of high blood pressure, heart attack and stroke.

“If people don’t eat ‘appropriately’, they get sick”

The higher the meat consumption, the higher the risks for cancer, diabetes and arteriosclerosis. What actually stands behind it: “If people do not eat ‘species-appropriate’, i.e. eat too much red meat and sausage and thus too much heme iron, they will get sick,” warns Matthias Riedl. It is well known that primitive peoples who still eat originally – eat very little meat and no sausage – do not have arteriosclerosis at all, for example.

Trivalent iron from plants is converted into bivalent iron

So heme iron has a rather negative effect on the body. Non-heme iron, on the other hand, does not pose these health risks – but is converted into bivalent iron in the body in order to make it available. Doesn’t it then become as unfavorable as bivalent heme iron? “No, because the trivalent iron from plants is converted into a bivalent iron, but not into heme iron,” explains the expert.

Providing the body with healthy iron – vegetables and fruits with non-heme iron

In order to provide the body with sufficient iron without meat, there are a number of plant-based foods that have a high content of non-heme iron, such as:

• Lentils around 2.7mg / 100gr
• Chickpeas around 2.7mg / 100gr
• Peas 1,5mg / 100gr
• Spinach 3,6mg / 100gr
• Chanterelles 6.5mg / 100gr
• Elderberry 1.6mg / 100gr
• Pine nuts 9.2mg / 100gr
• Millet 6.9mg / 100gr
• Flaxseed, ground 8,4mg / 100gr
• Amaranth 8.9mg / 100gr

Spinach contains a comparatively high amount of iron for a plant-based food, but at the same time the substances it contains can prevent it from being absorbed by the body. Beans or lentils are therefore better suited as a vegetarian source of iron.

Intelligently upgrade the bioavailability of iron from vegetables and fruits

Sure, none of these foods provide as much iron as meat. “The availability of iron from plant-based foods can be increased by cleverly combining the ingredients in a meal,” says Matthias Riedl. Vitamin C, for example, improves absorption. Suggestion for a corresponding daily plan:

• In the morning: oatmeal / muesli with fruit, a glass of orange or lemon juice for breakfast,
• Lunch: millet salad with paprika (the pods are extremely rich in vitamin C),
• In the evening: whole wheat pasta with broccoli or parsley pesto

Coffee and tea inhibit iron availability

However, there are also plant substances that have an inhibiting effect on iron absorption. These are phytates and polyphenols, for example, these plant substances are contained in coffee and tea. So avoid these drinks during, immediately before and after a meal containing iron. In wholemeal products, on the other hand, the phytate content plays a lesser role, as they convince with their high iron content.

Cover your iron requirement healthily, certain meats are also allowed

“Those who follow a purely vegetarian / vegan diet can still get too little iron, especially women are at risk here,” says the expert.

Pregnant and breastfeeding women in particular should take preparations if they have a proven iron deficiency. Otherwise there is a ‘species-appropriate’ solution for everyone: That means a small, moderate meat meal per week, preferably poultry meat, because white meat is not statistically associated with the disease risks mentioned.