Red Meat, Human Health and Climate Change

The control of climate change will ultimately depend on many small actions by each one of us. As doctors we are in an influential position to educate our patients into healthy lifestyles and to implement preventative medicine in our clinics. To our advice on smoking, alcohol, exercise and drugs, we must surely add advice on meat. This is an issue that will have a significant impact on the health of the individual and at the same time the on health of the planet by reducing greenhouse emissions. Let us look at the evidence.

A recent study in the Archives of Internal Medicine “A prospective study of meat intake and mortality in over  half a million people” determined the impact of the consumption of red, white and processed meat on total and cause-specific mortality.  Many possible confounding factors were studied. Red and processed meat intakes were associated with modest increases in total mortality, cancer mortality and cardiovascular disease mortality. These results complement the recommendations by the American Institute for Cancer Research and the World Cancer Research Fund to reduce red and processed meat intake to decrease cancer incidence.

This study builds significantly on many smaller studies conducted over the years which all demonstrate the health dangers of red meat. The case becomes overwhelming.  A New York Times editorial
 http://www.nytimes.com/2009/04/28/health/28brod.html?_r=2&pagewanted=print  discusses policy implications in the USA which are highly relevant to Australia because of our high meat consumption. Extrapolated to all Americans in the age group studied 50 to 71, it is suggested that over the course of a decade, the deaths of one million men and perhaps half a million women could be prevented. An Editorial in the Archives of Internal Medicine suggests red and processed meats be limited to twice a week, and non-vegetarians might consider eating poultry or fish.

A study of the environmental consequences of meat eating presents an unassailable need for change with meat requiring a huge consumption of water and producing a large proportion of the World’s agricultural greenhouse emissions. Not just the Amazon is being cleared for cattle grazing but around the world forest is being cleared for feed production (mainly soy) for the cattle. Land is being eroded. More pesticides are used and antibiotics contaminate water supplies. Over-all it is an environmental horror story. For a comprehensive review go to What's feeding our food The environmental and social impacts of the livestock sector” http://www.foe.co.uk/resource/briefings/livestock_impacts.pdf
If you read the full report and references, it is likely you will be into the peas, beans and lentils immediately.

A move to fish as a protein source for inhabitants of Western countries which is increasingly recommended for Omega-3 fatty acids should be examined carefully because of the overfishing, exploitation of developing country’s fisheries to make up the shortfall and the mercury content of some fish leading to warmings to pregnant women. Unfortunately mercury pollution which comes mainly from the coal industry can be expected to worsen.

How might this information translate into clinical practice?

Exploration of the patient’s meat intake should be on a par with the history of exercise, smoking and alcohol consumption. The doctor also has the opportunity and responsibility to assess the patient’s risk of nutritional disorders such as iron or B12 deficiency.  Dietary advice can therefore be tailored accordingly to the needs for each individual. 

 The patient should be informed that mortality increases in meat eaters because of hypertension, heart disease and several cancers.  A recommendation to avoid meat altogether may be counterproductive but for most Australians there should be encouragement to limit red and processed meat to two meals a week. In my experience this leads to a plaintive cry “Then what can I eat doctor?”

One has to be ready for this question and it requires some personal research if you are a meat eater yourself. For patients who have a risk of, or already have heart disease, I give them a Heart Foundation booklet on diet which explains concepts and suggests foods. I then ask the patient to bring questions to the next visit and often they do. To patients with other conditions, I touch on the matter when I go through the lifestyle issues and am often asked for an explanation. This allows me to explore fruit and vegetable intake, who does the cooking and how modest reforms can be instituted. For those committed patients who elect to eat no animal products (vegan), it is important that vitamin and mineral replacement needs to be discussed and planned.

Doctors for the Environment Australia does not yet have a leaflet that addresses this issue that you could give to all patients but we could consider one if there is demand from the members.