A new study out of Norway, published in February 2022, has presented more evidence that what we eat can give us extra years of healthy living. Using data from the Lancet 2019 Global Burden of Disease Study, researchers assessed the impact of food types on life expectancy by creating a model to illustrate the result of transitioning from a standard Western diet to an “optimal diet”. The optimal diet is substantially higher in fruits, vegetables, whole grains, legumes and fish than is the standard diet. It includes a handful of nuts daily and major reductions in red and processed meats, refined grains and sugar-sweetened beverages. (1)
Note: The 2019 Global Burden of Disease Study is an in-depth global study that analyzed 286 causes of death, 369 diseases and injuries, and 87 risk factors in 204 countries and territories to discover the greatest causes of healthy years of life lost and to estimate the burden they place on health care systems. (2)
Globally, dietary risk factors are estimated to cause 11 million deaths and 255 million years of poor health and disability every year (3). Many adults middle-aged and older worldwide are certainly living longer lives but those lives are often severely impaired by adverse health conditions (13). Yet navigating the field of nutrition to uncover the particulars of the effects of food on health can be overwhelming. Consider that, since 2017, approximately 250,000 scientific articles have been published on nutritionally related topics. The Global Burden of Disease Study, performed every few years since 1990, measures population health around the world and includes estimates for life years lost due to various dietary risk factors. However, comprehensive models are necessary to estimate the real-world influence of various dietary choices on lifetime health. That is where this modelling study estimating the impact of food choices on life expectancy comes in. Its aim was to determine the effect of sustained dietary changes on longevity. (1)
Study results show the potential for significant increases in life expectancy through healthier food choices (1).
Men who make a sustained change from the standard Western diet to an “optimal diet” could…
…add 13 years to their life if they started at age 20
…add 8.8 years to their life if they started at age 60
…add 3.4 years to their life if they started at age 80
Women who make a sustained change from the standard Western diet to an “optimal diet” could…
…add 10.7 years to their life if they started at age 20
…add 8 years to their life if they started at age 60
…add 3.4 years to their life if they started at age 80
Findings were similar for the United States, China and Europe.
The largest gains were made by eating more legumes, whole grains and nuts as well as through eating less red meat and processed meat; each of these variables could increase life expectancy by more than one year. Fruit, vegetable and fish consumption also had substantial impacts but their intake in a typical diet is closer to an optimal intake than for legumes, whole grains and nuts. (1)
The researchers concluded that, for those eating a typical Western diet, sustained dietary alterations towards a more optimal diet at any age can offer substantial health benefits although the gains are the largest if the modifications are started earlier in life. (1)
This information is not new but it substantiates the results of other previous science.
In 2014 a study involving almost 425,000 participants examined the relationship between four healthy dietary patterns and death as part of the NIH-AARP Diet and Health Study, finding that eating a healthy diet emphasizing whole grains, vegetables, fruit and plant-based proteins such as nuts and legumes was associated with a 12% to 28% reduction in death from all causes, cardiovascular disease and cancer in both men and women. (4,5)
The AARP Diet and Health Study published in 2020 followed over 400,000 US men and women aged between 50 to 71 years for 16 years and showed that higher dietary plant protein intake was associated with significantly reduced overall mortality and lowered death from cardiovascular disease in men and women. In particular, substituting egg protein with plant protein lowered the risk of death by 24% in men and 21% in women and substituting red meat protein with plant protein lowered the risk of death by 13% in men and 15% in women. (6)
A 2021 study also used the Global Burden of Disease study to develop an index for more than 5800 foods for their effects on minutes of healthy life lost or gained. Fruits, cooked grains and non-starchy mixed vegetables resulted in the highest gains of minutes of healthy life while processed meats and sugary drinks were linked to the greatest reduction in lifespan. In addition, a diet high in animal products was linked to increased risk of illnesses such as heart disease. (7)
Dr. David Katz, president and founder of the preventive and lifestyle medicine “True Health Initiative” commented that it has been long established that improving diet quality would reduce the risk of chronic disease and premature death and in doing so would also increase life expectancy. Furthermore, he pointed out that the “optimal diet” used in the 2022 study from Norway was much better than a typical diet, but still not the very best possible diet. (8) However, it is heartening to realize that even if dietary changes only go partway to being the healthiest they can be, lifespan can be increased. In addition, plant-based diets are associated with healthier years late in life with studies showing lower rates of cancer (9), 58% fewer medications required for chronic conditions (10) and improved sexual health (11).
Finally, we can’t forget the silver linings of adopting an optimal diet. People would enjoy not only a longer life, but also the opportunity to delight in healthy years and good quality of life throughout their lifetime all the way into old age. Governments around the world could breathe a collective sigh of relief as their exorbitant health care costs begin to recede. (13).
If you’re interested, the researchers responsible for the Norwegian modelling study created a public on-line tool, the Healthy4Life calculator, from their model to help professionals, policy makers and the general public understand the effects of diet on life expectancy. (12)
1 Fadnes, L.T., Økland, J.-M., Haaland, Ø.A., Johansson, K.A. Estimating impact of food choices on life expectancy: A modeling study. PLoS Med.022; 19(2): e1003889. Doi:10.1371/journal.pmed.1003889.
3 GBD 2017 Diet Collaborators. Health effects of dietary risks in 195 countries, 1990-2017: a systematic analysis for the Global Burden of Disease Study 2017. Lancet. 2019 May 11; 393(10184): 1958-1972.
4 Reedy, J., Krebs-Smith, S.M., Miller, P.E., Liese, A.D., et al. Higher Diet Quality is Associated with Decreased Risk of All-Cause, Cardiovascula Disease, and Cancer Mortality among Older Adults. J Nutr. June 2014; 144(6):881-889.
5 McCullough, M.L. Diet Patterns and Mortality: Common Threads and Consistent Results. J Nutr. June 2014; 144(6): 795-796.
6 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
7 Crosby, L., Davis, B., Joshi, S., Jardine, M., Paul, J., Neola, M., Barnard, ND. Ketogenic Diets and Chronic Disease: Weighing the Benefits Against the Risk. Front. Nutr. 16 July 2021; Doi.org/10.3389/fnut.2021.702802.
9 Gurjao, C., Zhong, R., Haruki, K., Li, Y.Y., Spurr, L.F., et al. Discovery and Features of an Alkylating Signature in Colorectal Cancer. Cancer Discov 2021; 11:2446–2455. Doi: 10.1158/2159-8290.CD-20-1656.
10 Dos Santos, H., Gaio, J., Durisic, A., Beeson, W.L., Alabadi, A. The Polypharma Study: Association Between Diet and Amount of Prescription Drugs Among Seniors. American Journal of Lifestyle Medicine. October 2021. Doi:10.1177/15598276211048812.
11 Kresch, E., Blachman-Braun, R., Nackeeran, S., Kuchakulla, M., Ramasamy, R. Plant Based Diets are Associated with Decreased Risk of Erectile Dysfunction. Journal of Urology: Sexual Function/Dysfunction: Medical, Hormonal & Non-surgical Therapy (PD20). 1 Sep 2021; 206(3): e368-e369. Doi.org/10.1097/JU.0000000000002009.05.
13 McGrath, R., Al Snih, S., Markides, K. et al. The burden of health conditions for middle-aged and older adults in the United States: disability-adjusted life years. BMC Geriatr. 2019;19(100). Doi.org/10.1186/s12877-019-1110-6.