New Zealanders eating “too much meat” again – What does the evidence say?
Once again we have headlines about how we need to cut back on meat consumption for the sake of our health, and the planet’s, fueled by a recent review. We’ve addressed the climate effects of ruminant agriculture before, this (most particularly with regard to intensive dairying and least of all with regard to sheep) is a conversation we need to keep having in NZ, but we would prefer experts to stop conflating this agenda with health advice.
As we’ll show, no-one has good data about how much meat New Zealanders currently eat, but past figures show that large numbers of Kiwis were deficient in the very nutrients that meat supplies in goodly amounts, making overconsumption unlikely. We’ll also present evidence that meat avoidance may have serious effects, which our health authorities may be overlooking.
It is not our position that vegetarian and vegan diets are intrinsically harmful; educated people with sufficient income, or people with sound cultural support in the case of traditional vegetarian diets, are those most likely to eat nutritionally adequate diets without meat, or with little meat. But meat and other animal foods are so nutrient dense as to be dietary fail-safes for the majority of people who do not have time, inclination, money, or education to guarantee good nutrition otherwise, as we will see. Random advice to cut these foods from the diet, delivered without nuance as primetime TV News, can only harm the most vulnerable members of society.
How much meat is in our “high meat” diet?
New Zealand authorities have not calculated the amount of meat in our diets since the 2008/2009 Health and Nutrition Survey. (another survey was done since, but the only diet questions in it were about one about sugary soft drink consumption and one about getting 5+ servings of fruit and vegetables a day).
According to the 2008/2009 nutrition survey, the protein intakes estimates of New Zealanders were 16.4% and 16.5% of energy for males and females respectively, at the lower end of dietary recommendations of 15-25%.
Bread and other grain-based foods supplied nearly a third of our protein intake, only a fifth of which came from red meat, processed meat, and pork. (We calculate this as an average of only 16.5 grams of meat protein per day in a 2,000 kcal diet).
Similarly, meat contributed significantly less iron to the diet (about 13%) than bread, pasta, and breakfast cereals (29%). These figures do not indicate a population overeating meat; if anything, they seem to indicate a population overly reliant on refined wheat in all its forms (only the processed forms of grains, which are supplemented, are a good source of iron).
When these results were published in 2011, Professor Elaine Rush, Professor of Nutrition, Faculty of Health and Environmental Science, Auckland University of Technology made the following comments on the Science Media Centre blog:
The biggest whammy is for people living in more deprived areas. They are more likely to be overweight or obese, not meeting recommended micronutrient intakes such as iron, vitamin A and calcium. Bread continues to be the major contributor of energy, protein, and carbohydrate to the New Zealand diet, In comparison to white bread, light or heavy whole grain bread was chosen by 60% of the population, but almost 50% of young adults compared to 25% of older people reported eating white bread. The most socioeconomically deprived 20% were twice as likely to consume white bread compared to the most well off 20% (20% vs 40%).
The evidence is clear, in 2008 New Zealanders were not well nourished, many did not have enough money to buy nutritionally adequate and safe foods and were not healthy. Since then the economic recession and the ever-increasing cost of food mean that we are unlikely to be improving. More importantly our present children and those still to be conceived are not likely to have an optimal start to life continuing the cycle. A whole of New Zealand response is required because it is not a personal choice or responsibility- particularly for children. We produce enough good food to feed everyone well – why the gap between the farm and the mouth?
Why indeed? Our red meat exports are higher than ever, yet this seems to be diverted away from our population. Zinc seems to be very much an indicator of animal food (red meat, shellfish, and cheese) consumption in the MOH report, as no good plant sources of zinc are listed.
Nearly a quarter (24.7 percent) of New Zealanders aged 15 years and over were not getting enough of the trace element zinc in their diet, with 39.1 percent of men and 11.2 percent of women missing out. The median usual daily intake of zinc was 12.9mg for men and 9mg for women, and even lower for older people. These intakes were down on those seen in the 1997 survey.
As the RDI of zinc is 14mg per day for men and 8mg/day for women, this means that most men and almost half of women in NZ were below the RDI for zinc in 2008/2009. Hardly a population eating too much meat back then, but we don’t know if this is even worse today. And there’s the problem – experts racing off making blanket recommendations when there is insufficient data about the current position.
Adverse effects of meat avoidance – mental health.
We have serious concerns about the effect of meat avoidance at a population level as a public health-endorsed recommendation, whether the reason for it is ethical, socio-political, environmental, or flat-out poverty. Such advice needs to meet robust criteria for cause and effect, the effect needs to be strong and with little chance harm occurring with populations taking such recommendations.
The study by Hibbeln et al that found increased rates of depression in vegetarian men cites six other studies with similar findings, including two in adolescents. Only one cited study, in US Seventh Day Adventists – a relatively privileged group which plays an important role in the promotion of meat avoidance – had different results.
Another study by Hibbeln et al found that vegetarianism in pregnancy was associated with substance abuse (alcohol and cannabis) in offspring, and screening for the effect of a vitamin B12 absorption allele increased confidence that the relationship was causal (there was no association by diet in those who had genetically poor B12 absorption whatever their diet).
A survey of patients with anorexia nervosa found that vegetarians and vegans were over-represented and were more likely to have a persistent condition.
Compared to controls, individuals with an eating disorder history were significantly more likely to ever have been vegetarian (52% vs. 12%), to be currently vegetarian (24% vs. 6%), and to be primarily motivated by weight-related reasons (42% vs. 0%). The three recovery status groups (fully recovered, partially recovered, active eating disorder) did not differ significantly in percentiles endorsing a history of vegetarianism or weight-related reasons as primary, but they differed significantly in current vegetarianism (33% of active cases, 13% of partially recovered, 5% of fully recovered). Most perceived that their vegetarianism was related to their eating disorder (68%) and emerged after its onset.
The associations between meat avoidance and mood disorders in these studies are strong – they certainly dwarf any associations drawn between meat and any other diseases. We acknowledge this alone doesn’t demonstrate cause and effect. But it does suggest that there is a possibility of harm, and we must be cautious with population-wide advice.
New Zealand needs data on these correlations from within its own population before our public health experts start recommending meat avoidance to a population which has so many vulnerable members, in a country which is facing a mental health crisis.
Meat and cancer, Part 2 (Part 2).
The review goes lightly into the meat and colon cancer association, without a very clear discussion of the stats or the hopelessness of the “processed meat” definition. We’ve discussed this data before, but we’d like to share a much stronger and more convincing association – in 2006 people being treated for colon cancer, the insulin load and insulin index of the diet (a measure of the amount of insulin required to metabolise the food) was strongly correlated with cancer mortality.
The adjusted HRs for CRC-specific mortality comparing the highest to the lowest quintiles were 1.82 (95% CI: 1.20-2.75, Ptrend=0.006) for dietary insulin load and 1.66 (95% CI: 1.10-2.50, Ptrend=0.004) for dietary insulin index. We also observed an increased risk for overall mortality, with adjusted HRs of 1.33 (95% CI: 1.03-1.72, Ptrend=0.03) for dietary insulin load and 1.32 (95% CI: 1.02-1.71, Ptrend=0.02) for dietary insulin index, comparing extreme quintiles. The increase in CRC-specific mortality associated with higher dietary insulin scores was more apparent among patients with body mass index (BMI)⩾25 kg m-2 than BMI<25 kg m-2 (Pinteraction=0.01).
Now, while it’s true that protein requires insulin to be metabolised and that beef has a relatively high insulin load, it is also true that people eating low-carb diets get insulin levels very low whether they eat meat or not; such diets certainly reverse hyperinsulinaemia. Refined carbs are simply going to drive up the insulin effect of other foods like beef; you need protein and vitamins and minerals, and you don’t need sugar and artificial colourings.
It’s refined carbohydrate, sugar and starch, not protein or fat, which is most likley wasting the health of New Zealanders. We can demonstrate this by the improvements in health we see every day when people limit sugar and starch in their diets; not just biomarkers, but improvements in mood, pain, and exercise capacity. The health benefits of carbohydrate restriction are becoming more generally known and accepted with time.
The realisation that sugar and starch are fundamental to the nutrition-related harm that occurs in populations of developed countries is becoming mainstream now. The recent BMJ special issue “Food for Thought” is swimming in the science and policy of such a realisation.
There may even be environmental benefits; for one thing, you can now eat the fat from an animal instead of wasting it and replacing it with another food, for another thing, weight loss is a common side-effect of LCHF, even when used as a migraine cure.
And excess weight means people need to eat more. In 2012, biomass due to obesity was 3.5 million tonnes, the equivalent of 56 million people of average body mass (1.2% of human biomass globally). If the obesity epidemic could be entirely reversed, the food savings would be roughly equivalent to the annual food consumption of Australia and Canada combined (minus that of little New Zealand). This is perhaps a drop in the bucket globally, but it is still a lot of people.
Of course, we can treat and farm animals better and be more sustainable. That’s what the apex omnivore – us humans – must do if we want to leave even a half decent planet for the next generations.
 Godfray HCJ, Aveyard P, Garnett T et al. Meat consumption, health, and the environment. Science. 2018 Jul 20;361(6399). pii: eaam5324. doi: 10.1126/science.aam5324.
 Hibbeln JR, Northstone K, Evans J, Golding J. Vegetarian diets and depressive symptoms among men. J Affect Disord. 2018 Jan 1;225:13-17. doi: 10.1016/j.jad.2017.07.051. Epub 2017 Jul 28.
 Hibbeln JR, SanGiovanni JP, Golding J, et al. Meat Consumption During Pregnancy and Substance Misuse Among Adolescent Offspring: Stratification of TCN2 Genetic Variants. Alcoholism: Clinical & Experimental Research. Published online October 4 2017
 Bardone-Cone AM, Fitzsimmons-Craft EE, Harney MB, et al. The Inter-relationships between Vegetarianism and Eating Disorders among Females. Journal of the Academy of Nutrition and Dietetics. 2012;112(8):1247-1252. doi:10.1016/j.jand.2012.05.007.
 Yuan C, Bao Y, Sato K et al. Influence of dietary insulin scores on survival in colorectal cancer patients. Br J Cancer. 2017 Sep 26;117(7):1079-1087. doi: 10.1038/bjc.2017.272. Epub 2017 Aug 17.