Eat More Plant Protein for a Longer Life

Protein is a popular topic of conversation these days.  In spite of the fact that most North Americans today consume too much protein, a common worry is whether or not people are getting enough protein from their diet.  Much more important for health though is the source from which dietary protein is obtained.

Brand new science on this topic was published during July 2020.  Two separate studies found that eating protein from plants increases longevity compared to eating protein from animals.

 

The First Study:  Published in the Journal of the American Medical Association on July 13, 2020 (1)

This research draws on data from the National Institutes of Health – AARP Diet and Health Study.  Participants included over 400,000 US men and women aged between 50 to 71 years who were followed for sixteen years.  This is a prospective cohort study, a powerful observational study that carries the greatest strength in terms of level of evidence relative to other observational study designs.

Results are as follows;

• Higher dietary plant protein intake was associated with reduced overall mortality and lower death from cardiovascular disease in both men and women.
• Replacing 3% of energy from animal protein with plant protein was associated with 11% lower risk of death from cardiovascular disease in men and a 12% lower risk in women
• Replacing 3% of energy from animal protein with plant protein was associated with 10% decreased risk in overall mortality in both men and women
• Replacing 3% of energy from eggs with plant protein was associated with 24% decreased risk in overall mortality in men and 21% in women
• Replacing 3% of energy from red meat with plant protein was associated with 13% decreased risk in overall mortality in men and 15% in women

 

In addition, the benefits accumulated as more plant protein was consumed.

• A 12% reduction in mortality risk was seen in men for every 10 grams of plant protein consumed per 1000 calories of food intake
• A 14% reduction in mortality risk was seen in women for every 10 grams of plant protein consumed per 1000 calories of food intake

 

The Second Study:  Published in the British Medical Journal on July 22, 2020 (2)

This research is a meta-analysis that compared results from 32 previous prospective cohort studies encompassing over 700,000 adult participants.  Researchers from Harvard University, Tehran University of Medical Sciences, the Brigham and Women’s Hospital and Harvard Medical School looked at the effect of plant-based dietary protein on early death from any cause and death from heart disease and cancer.

The results are as follows;

• The highest total protein intake was linked to a lower risk of death from all causes compared to the lowest levels of protein intake.
• Higher intake of plant protein was significantly associated with an 8% lower risk of early death from all causes and a 12% lower risk of death from cardiovascular disease.  This association remained significant after controlling for energy intake, BMI, macronutrient intake and studies that assessed the diet through food frequency questionnaires.
• The addition of 3% of calories from plant proteins daily was associated with a 5% lower risk of death from all causes.

These new results support previous findings on the benefit of eating plant-based protein over protein derived from animals

The Harvard Health Professionals Study from 2016 included over 131,000 participants followed for 27 to 30 years and found that replacing 3% of calories from animal protein with plant protein reduced risk of death as follows (3);

• Replacing processed meat with plant protein resulted in a 34% reduction in risk of death
• Replacing eggs with plant protein resulted in a 19% reduction in risk of death
• Replacing unprocessed red meat with plant protein resulted in a 12% reduction in risk of death
• Replacing dairy with plant protein resulted in an 8% reduction in risk of death
• Replacing poultry or fish with plant protein resulted in a 6% reduction in the risk of death.

 

A 2019 prospective study from the Japan Public Health Center followed over 70,000 healthy 45 to 74-year-olds for 17 to 21 years and discovered that replacing 3% of calories from meat with plant protein resulted in lower mortality.

• When red meat was replaced with plant protein, total mortality decreased by 34% and cancer mortality decreased by 42%.
• When processed meat was replaced with plant protein, total mortality decreased by 46% and cancer mortality decreased by 50% (4).

 

Conclusion

Most people yearn to live a life that is as long and disease-free as possible.  These two studies illustrate that increasing intake of plant-based foods and lowering intake of animal-based foods is likely to have a substantial positive impact on reaching that goal.

 

SOURCES:

1  Huang J, Liao LM, Weinstein SJ, Sinha R, Graubard BI, Albanes D. Association between plant and animal protein intake and overall and cause-specific mortality. JAMA Intern Med. July 13, 2020. Doi:10.1001/jamainternmed.2020.2790

2  Naghshi, S., Sadeghi, O., Willett, W.C., Esmaillzadeh, A. Dietary intake of total, animal, and plant proteins and risk of all cause, cardiovascular, and cancer mortality: systematic review and dose-response meta-analysis of prospective cohort studies. BMJ. 2020;370:m2412-m2429.

3  Song M, Fung TT, Hu FB, et al. Association of Animal and Plant Protein Intake With All-Cause and Cause-Specific Mortality. JAMA Intern Med. 2016;176(10):1453-1463. doi:10.1001/jamainternmed.2016.4182

4  Budhathoki S, Sawada N, Iwasaki M, et al. Association of Animal and Plant Protein Intake With All-Cause and Cause-Specific Mortality in a Japanese Cohort. JAMA Intern Med. 2019;179(11):1509-1518. doi:10.1001/jamainternmed.2019.2806