Australasian Science: Australia's authority on science since 1938

Does Red Meat Deserve Its Bad Reputation?

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Because Australian red meat differs so significantly from other western countries, we need to be very careful about interpreting the results of major studies examining health outcomes associated with red meat intake.

By Amanda Patterson

Returning to the tradition of eating “meat and three veg” for dinner may improve the eating patterns and nutritional status of Australians, and help to reduce rates of chronic disease.

Red meat is an excellent source of iron and zinc, vitamin B12, good quality protein, niacin, vitamin B6 and phosphorus. In fact, a 100 gram serving provides more than 25% of the Recommended Dietary Intake for each of these nutrients. Red meat is also a significant contributor to intakes of omega-3 fatty acids, riboflavin, pantothenic acid and selenium. Despite this extraordinary contribution to nutrient intakes, red meat has received bad press for the past three decades or more.

Fatty red meat has been linked to increased LDL cholesterol levels and heart disease in the past, but Australia’s pattern of meat consumption has changed significantly. We now choose leaner cuts of red meat and remove separable fat. Consumer preferences for lean meat have seen changes to the production of meat in terms of breeding, feeding practices and modern butchery techniques, so that the proportion of separable fat has declined significantly. For Australians who regularly trim this separable fat, the lean meat they consume is typically less than 7% fat – a similar fat content to a dry whole-wheat cracker and significantly less than a typical muesli bar.

The 1995 National Nutrition Survey, Australia’s most recent source of national dietary data for adults, found that adult men and women consumed 99 grams and 54 gram of red meats per day, respectively. While these values may not sound high, they do make us one of the highest consumers of red meat worldwide.

However, it is important to understand that Australian meat differs significantly to other parts of the world. Almost all of our livestock are pasture-fed rather than grain- and lot-fed, as in the US, which marbles fat throughout the meat. Pasture-fed meat is much leaner with a better fatty acid profile, including a higher proportion of polyunsaturated fatty acids. In particular, Australian red meat has a relatively high proportion of omega-3 fatty acids and is the second greatest contributor of omega-3 in the Australian diet.

Because Australian red meat differs so significantly from other western countries, we need to be very careful about interpreting the results of major studies examining health outcomes associated with red meat intake. We must also be careful to make the distinction between fresh red muscle meat, such as steak or lamb, and‘processed meats or meat products, such as deli meats, bacon, sausage and offal. Much of the research internationally does not clearly make this distinction, making interpretation in the Australian context difficult.

Despite these limitations and the bad press, there is actually some good evidence for the inclusion of lean red meat in the diet in relation to weight management, Type 2 diabetes, hypertension and cardiovascular disease. High protein, low energy diets are more satiating and result in greater fat loss than high carbohydrate weight loss diets. They also appear to achieve better blood fat and blood sugar results in diabetes management than high carbohydrate diets.

Red meat has also proven to be less cholesterol-raising than previously estimated due to the effects of stearic acid, repeatedly showing little or no cholesterol-raising effect. Red meat is low in sodium and high in potassium, and human dietary experiments have found that it doesn’t raise blood pressure.

The one area where the evidence appears to be against red meat is in relation to the risk of colon cancer. The World Cancer Research Fund in 2007 found that the evidence was “convincing for an increased risk” of colorectal cancer with high meat and processed meat intakes, and this finding has been supported by further studies since then. The National Health and Medical Research Council of Australia incorporated this evidence into the latest release of the Australian Dietary Guidelines, and suggested that red meat intake be limited to 455 grams per week (one serve or 65 grams cooked weight per day). Based upon the National Nutrition Survey data, this is a decrease for Australian men but an increase for women, which may have health benefits for women in relation to iron deficiency and mental health.

Iron deficiency is the most common nutrient deficiency worldwide. At greatest risk are women of childbearing age and young children: 20% of women (25–50 years) in Australia and 14–25% of infants and children (up to 3 years) are iron-deficient. This can affect physical functioning, exercise tolerance and immunity, and adversely affects behavioural development and cognitive functioning in infants and children. The full effects on cognition in adults are not yet clear, but two significant studies found that general health and well-being (including mental health) was reduced and fatigue levels increased for Australian women.

Dietary iron is found in two forms. Haem iron is found in flesh foods only, with concentrations in red meat significantly higher than in chicken and fish. Around 11–22% of haem iron is absorbed, while only 1–7% of non-haem iron from vegetable and cereal sources is absorbed. Subsequently, studies show that while the body’s iron levels are not related to total dietary iron intake, they are influenced by haem iron intake. In addition, iron deficiency has been successfully treated with diets that increase lean red meat intakes.

An emerging research area is on dietary patterns and mental health outcomes, including anxiety and depression. Recent Australian research has shown that women who were eating less than the recommended amount of red meat were twice as likely to have a diagnosed depressive or anxiety disorder than those who were eating the recommended amount. These results could be due to better omega-3 intakes or better iron intakes, or any combination of the essential micronutrients found in red meat.

We know that women in Australia who eat more fresh meat, including red meat, chicken and fish, also eat more vegetables. Our research group at the University of Newcastle has shown this in over 10,000 middle-aged women (50–55 years) from the Australian Longitudinal Study of Women’s Health (ALSWH), and published the results in the journal of the Dietitians Association of Australia. We recently repeated the analysis with over 9000 young women (25–30 years) from the ALSWH and found the same thing – those with higher fresh meat intakes had better intakes of vegetables.

Inadequate vegetable intake is a major public health concern, and increasing intakes of vegetables is key to addressing obesity and chronic disease. Many of us who are more than 40 years old remember growing up on meals of “chops and veg” or “steak and veg”,and while the meats might have been fattier than what we would recommend now, we were mostly good veggie eaters.

Returning to the traditional Australian “meat and three veg”, with our leaner and easier to cook cuts for dinner on several nights of the week, may just be one way to increase the vegetable intakes of Australians, especially Australian children, while at the same time decreasing the salt and fat content of the evening meal and ensuring adequate intake of key nutrients such as iron, zinc, B12 and omega-3. This may also have advantages for helping to stem the obesity epidemic, decrease the rates of heart disease and diabetes and improve the mental health of Australians.

While much more research is needed, we do know that for Australian women and children, increased intakes of lean red meat are likely to help decrease rates of iron deficiency and improve general health and well-being in women and cognition in children.

Dr Amanda Patterson is a lecturer in nutrition and dietetics at the University of Newcastle, and an accredited practising dietitian with a research background in iron deficiency and women’s health.