If You Eat Healthy for the Planet, Do You Also Eat Healthy for the Human?

In 2019, the EAT-Lancet Commission gained headlines worldwide when it proposed a healthy dietary pattern that, along with reductions in food waste and improved agricultural practices, could feed the increasing global population sustainably.

Now a Planetary Health Diet Index (PHDI) has been developed to quantify adherence to the EAT-Lancet reference diet.  Does the EAT-Lancet diet benefit human health along with planetary health?  A new study has been published that reports on this. 

The study aimed to assess associations between PHDI and total and cause-specific mortality in 3 prospective cohorts of males and females in the United States.

The researchers followed 66,692 females from the Nurses’ Health Study (1986–2019), 92,438 females from the Nurses’ Health Study II (1989–2019), and 47,274 males from the Health Professionals Follow-up Study (1986–2018) who were free of cancer, diabetes, and major cardiovascular diseases at baseline.

The PHDI was calculated every 4 y using a semiquantitative food frequency questionnaire.

 

 

During follow-up, there were 31,330 deaths among females and 23,206 among males.

When those that were highest in the PHDI were compared to the lowest group, there was a 23% lower rate of death of all causes.

The PHDI was associated with lower risk of deaths from cardiovascular diseases (by 14%), cancer (by 10%), respiratory diseases by 47%), and neurodegenerative diseases (by 28%).

 

High PHDI scores were also associated inversely with greenhouse gas emissions and other environmental impacts.

 

In 3 large United States-based prospective cohorts of males and females with up to 34 y of follow-up, a higher PHDI was associated with lower risk of total and cause-specific mortality and environment impacts.

 

This study suggests that learning to eat healthy for the planet with a plant based approach is also healthy for the human body.

 

The planetary health diet is flexible by providing guidelines to ranges of different food groups that together constitute an optimal diet for human health and environmental sustainability. It emphasizes a plant-forward diet where whole grains, fruits, vegetables, nuts and legumes comprise a greater proportion of foods consumed. Meat and dairy constitute important parts of the diet but in significantly smaller proportions than whole grains, fruits, vegetables, nuts and legumes.

In addition to the targets set within each section, the dietary targets also suggest that the average adult requires 2500 kcal per day. While this amount will vary based on age, gender, activity levels and health profiles, overconsumption is a waste of food with both health and environmental costs.