Metabolic Health Mythbusting: Meat Consumption Does Not Explain Differences in Household Food Carbon Footprints in Japan

2018.05 Low Carb and Low Carbon - Ted Eytan MD-1001 848
2018.05 Low Carb and Low Carbon – Ted Eytan MD-1001 848 (View on Flickr.com)

I have been observing people being told that they must reduce their meat consumption for planetary health, regardless of their metabolic health status, regardless of the other determinants of their dietary and overall carbon footprint. Same goes for workplaces adopting policies like this for planetary (but not human) health reasons.

Just as “one size fits all” is unhelpful for health, there cannot be the same attitude toward personal or workplace carbon footprint. This approach is not well informed at best and disrespectful at worst. We are in a climate emergency and every human and employer is capable and responsible for working to mitigate climate change as well as their own health, whether or not they consume meat. Both, not one or the other.

The Study

This is a clever study that examined the dietary carbon footprints of 60,000 households in Japan, stratifying the drivers of differences between high carbon and low carbon households. While it is recognized that meat has higher greenhouse gas emission intensity relative to other foods, this study found that 9% of the difference in carbon footprint between the highest and lowest quartile carbon emitting households was contributed to by meat.

Higher carbon footprint households had a smaller percentage of their footprint derived from meat, and households generally had the same amount of meat consumption in this sample, regardless of income group.

….as it is not widely known or discussed that alcohol, confectionery, and restaurants meals in fact substantially differentiate high-carbon footprint households, simply communicating this message could provide surprising and helpful information to households seeking to reduce their dietary carbon footprint.Kanemoto K, Moran D, Shigetomi Y, Reynolds C, Kondo Y. Meat Consumption Does Not Explain Differences in Household Food Carbon Footprints in Japan. One Earth [Internet]. 2019 Dec;1(4):464–71

Minimal impact of income or savings amount on carbon footprint

The researchers tested the hypothesis that drivers of dietary carbon footprint were based on income level, and found only a weak association.

We analyzed whether there is correlation between income or savings and household food CF. The results indicate there is a positive, albeit weak, correlation between the two.Kanemoto K, Moran D, Shigetomi Y, Reynolds C, Kondo Y. Meat Consumption Does Not Explain Differences in Household Food Carbon Footprints in Japan. One Earth [Internet]. 2019 Dec;1(4):464–71

Study authors feel data is generalizable and are not “pro-meat”

The authors point out that Japan’s meat consumption is much less than comparable countries, such as the United States, and cite this as a virtue of the study:

Though the country has a unique cuisine, the composition of the current typical Japanese diet is similar what other national health organizations recommend,35 i.e., high consumption of soy and isoflavones, fish and n-3 fatty acids, and green tea, and low consumption of red meat and saturated fat.

The authors, if anything, have an intellectual bias against meat from my read, given the statement above and favorable inclusion of the deeply controversial EATLancet report.

I decided to look up the data for myself from FAO and OECD sources, and indeed, it shows Japan with steadily increasing meat consumption per capita, but still far less than the United States or Hong Kong, for example. The OECD chart does not include Hong Kong, but does show variation in the types of meat consumed.

2020.01.01 Food Balance - Food Supply - Livestock and Fish Primary Equivalent, FAO Stat 005 01012
2020.01.01 Food Balance – Food Supply – Livestock and Fish Primary Equivalent, FAO Stat 005 01012 (View on Flickr.com)

Valuing people and their values – carbon footprint is as personal as health status

In my review of many of these modeling studies,I find they share the same flaw, which is that they cannot account for every food or other behavior in a household. It’s impossible to know all of the variables that contribute to a person’s carbon footprint, which therefore makes blanket statements like “eat less meat,” in the setting of carbon as meaningless to a person/family as “eat less” or “exercise more” in the setting of health.

Many studies, including the EAT-Lancet Commission report, have argued that changing diets—in particular, shifting away from beef in favor of white meat and vegetables—can substantially reduce household carbon footprints (CFs). This argument implies that households with high CFs consume more meat than low-CF households. An observation of diet and CF across 60,000 households in Japan, a nation whose diet and demographics are in many ways globally indicative, does not support this.Kanemoto K, Moran D, Shigetomi Y, Reynolds C, Kondo Y. Meat Consumption Does Not Explain Differences in Household Food Carbon Footprints in Japan. One Earth [Internet]. 2019 Dec;1(4):464–71

Start with metabolic health first

Here is my carbon footprint as I’ve calculated it. As I discussed in this blog post (See: Calculating carbon footprint as a non-diabetic physician on an LCHF diet), many of the assumptions in the dietary portion are based on a person who snacks throughout the day and eats ultra-processed food. I did my best to account for this in my dietary calculation. As you can see though, this is still a small percent of the overall footprint.

2018.05 Low Carb and Low Carbon - Ted Eytan MD-1001 793
2018.05 Low Carb and Low Carbon – Ted Eytan MD-1001 793 (View on Flickr.com)

A physician should discuss all the ways a person can achieve and maintain metabolic health first. Then, they should do the same for a person’s carbon footprint. Physicians need to be conversant in both spaces. Unfortunately, very few are conversant in either, for now.

Climate conversations in the workplace, too

As a physician may collaborate with a person, employers should collaborate with their workforce, to look at the determinants of carbon emissions in that setting. The same advice applies, which is that a “no meat” blanket policy may omit consideration of all of the other drivers of food-based emisisons, and non-food based emissions as well.

This is especially true given the unintended consequences I’ve seen from policies that don’t take into account individual environments: Slide Update: Metabolic Health Status, United States Adults, and why it matters when thinking about a “no meat” workplace.

We have to look at everything holistically.

Healthy people need a healthy planet, vice versa, and not one or the other.

Disclosed conflicts of interest in the study

None

References

  1. Kanemoto K, Moran D, Shigetomi Y, Reynolds C, Kondo Y. Meat Consumption Does Not Explain Differences in Household Food Carbon Footprints in Japan. One Earth [Internet]. 2019 Dec;1(4):464–71.
  2. OECD (2020), Meat consumption (indicator). doi: 10.1787/fa290fd0-en (Accessed on 05 January 2020).
  3. Food Balance – Food Supply – Livestock and Fish Primary Equivalent – FAOStat

My Disclosures

They can be found here (I have none). In terms of intellectual bias, I am not vegan, I am not carnivore, I am somewhere in the middle (along with 97% of the US population). I am formerly fat and follow a low carbohydrate, real food, healthy fat eating approach.

What questions do you have about metabolic health?

Ask me in the comments 🙂

Ted Eytan, MD