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Opened walnuts that when eaten regularly show some longevity and health benefits

Eating Walnuts May Extend Your Life

Harvard scientists recently found that 60-year-olds who ate five weekly servings of walnuts had a 1.3-year increase in lifespan. Walnuts may protect against diabetes, cancer, and Alzheimer’s.

Scientifically reviewed by: Dr. Gary Gonzalez, MD, in May 2022. Written by: Michael Downey.

Walnuts provide an array of health benefits.

New evidence suggests that regular walnut consumption may contribute to a longer life.1

In a landmark study using data collected over 20 years, scientists with Harvard University discovered a link between eating more walnuts and a lower overall risk of death among older adults.

This observational study found that 60-year-old Americans who ate five or more servings of walnuts per week lived roughly 1.3 years longer than those who never ate walnuts.1

They also had a 14% lower risk of death from any cause and a whopping approximate 25% lower risk of dying from cardiovascular disease.

Longer Lifespan

Walnuts contain healthy fats, fiber, vitamins, minerals, and many different compounds with proven health benefits.

Harvard research published in the journal Nutrients in 2021 now links walnuts to greater life expectancy.1

Compared to people who never ate walnuts, consuming five servings of walnuts per week (with one serving being one ounce) resulted in:1

  • An approximate 1.3-year increase in life expectancy, for 60-year-olds,
  • A 14% lower risk of death from any cause, and
  • A 25% lower risk of dying from cardiovascular disease.

Consumption of just two to four servings of walnuts per week also had clear benefits, resulting in:1

  • About a one-year increase in lifespan, for 60-year-olds,
  • A 13% lower risk of death from any cause, and
  • An approximate 14% lower risk of death from cardiovascular disease.

The study authors noted that even if your diet needs improvement, eating just half an ounce (a half-serving) of walnuts daily could lower the risk of death from any cause by 12%.

Twenty Years of Study Data

The team from the Harvard T.H. Chan School of Public Health analyzed data from 67,014 women enrolled in the Nurses' Health Study and 26,326 men in the Health Professionals Follow-up Study. Participants had an average age of just over 63 years.1

All subjects had completed a survey on walnut consumption and were relatively healthy at the start of the average 20-year follow-up period. Their diets were checked every four years. This allowed scientists to identify associations between varying levels of walnut intake and life expectancy.

It's important to note that the researchers found an approximate 1.3-year increase in life expectancy associated with higher walnut consumption—among subjects who had already reached the age of 60.1

"Even a few handfuls of walnuts per week may help promote longevity," noted lead investigator Yanping Li, PhD, "especially among those whose diet quality isn't great to begin with."2

Nutritional Powerhouse

Walnuts contain nutrients that play an important role in a healthy diet. One ounce contains 4 grams of protein, 2 grams of fiber, and 45 mg of the mineral magnesium.3

They also contain ALA (alpha-linolenic acid), an omega-3 fatty acid found in plants.3

ALA may improve blood lipids (fats)4-6 as well as the function of endothelial cells that line the arteries.7-9

Walnut consumption has also been associated with reduced oxidative stress.10,11

These nutritional contents may help explain walnuts' contribution to healthy aging and longevity.

Walnuts' powerful effects on lifespan and risk of death may result from their ability to help inhibit many conditions that can shorten lifespan. These conditions range from high blood pressure and obesity to diabetes and cancer.

What you need to know

The Benefits of Walnuts

  • Harvard researchers analyzed 20 years of data on over 93,000 older men and women and found that those who ate a one ounce serving of walnuts five times a week lived roughly 1.3 years longer than those who didn’t eat walnuts.
  • Those who ate five weekly servings of walnuts had a 14% lower risk of death from any cause and a 25% lower risk of dying from cardiovascular disease.
  • Other studies suggest that walnut consumption may help protect against heart disease, control type II diabetes, and potentially help lower the risk of Alzheimer’s disease and several types of cancer.

Heart Protection

Walnuts are believed to reduce the risk of cardiovascular disease.12

One possible reason is that walnut consumption is linked to a reduction in blood pressure, even among those with existing hypertension.13

High blood pressure is a key risk factor for heart disease and stroke.

High cholesterol levels can also result in the development of vascular disease.

Preclinical data suggest that walnuts may reduce the production of lipids and improve blood lipid levels.14

In a randomized controlled trial, a diet enhanced with 1.5 ounces of walnuts daily significantly reduced fasting levels of multiple atherogenic lipids and lipoproteins, including total cholesterol, non-HDL cholesterol, LDL-cholesterol, triglycerides, and apoB (apolipoprotein B).15

Another clinical trial of healthy adults between 63 and 79 years old showed that eating about two ounces of walnuts daily for two years:16

  • Reduced total cholesterol, LDL and IDL (Intermediate Density Lipoprotein),
  • Reduced total LDL particles number by 4.3%, and
  • Reduced total small LDL particles number (a more dangerous form of LDL) by 6.1%.

Help Controlling Diabetes

Type II diabetes is dangerous for its potential long-term complications, including cardiovascular disease, chronic kidney disease, nerve damage, vision problems, and cognitive impairment.17,18

Accumulating evidence suggests that walnuts and their components may help lower blood sugar and reduce the long-term health ris associated with diabetes.19

A human trial found that consumption of walnut oil daily for three months lowered blood sugar levels in diabetes patients by about 8%. This held true for both the fasting glucose level and the three-month (HbA1c) blood glucose level.20

A flavonoid in walnuts called myricetin has been linked to antidiabetic effects due to its ability to enhance the activity of an insulin receptor.21

Anti-Cancer Activity

Limited evidence suggests that walnut consumption may lower the risk of certain cancers.

In one lab study, walnuts' peptide fractions inhibited the growth of breast cancer cells by about 63% and colon cancer cells by about 51%.22

Animal studies have found that feeding walnuts to mice inhibits the development of tumors and decreases tumor growth rate and size.23

One analysis compared the estimated lifelong consumption of walnuts, peanuts, and almonds of breast cancer patients with people free from breast cancer. Compared to those with no consumption, those with high consumption had a two to three times lower risk of breast cancer.24

Brain Health

Lab and animal studies show that compounds present in walnuts reduce oxidative damage and inflammation in brain cells.25 In a mouse model of Alzheimer's disease, walnuts reduced oxidative damage to lipids and proteins.26

In an animal model of Alzheimer's disease, mice were fed walnuts for about 10 months, a significant portion of their lifetimes. Compared to mice given no walnuts, they showed improvements in memory, learning ability, and more.27

Additional research suggests that walnuts may also lower the risk or progression of other brain disorders, including Parkinson's disease, stroke, and depression.28

Adding a handful of walnuts to your daily diet appears to be a simple way to improve overall health and possibly even extend your lifespan.

Summary

A recent, large study by Harvard University scientists found that 60-year-olds, eating five weekly servings of walnuts, had an approximate 1.3-year increase in lifespan.

There was also a 14% lower risk of death from any cause and a 25% lower risk of dying from cardiovascular disease.

Some longevity benefits were found even with fewer weekly servings of walnuts.

Other studies suggest that regular walnut consumption may protect against hypertension, high cholesterol, diabetes, cancer, and Alzheimer's disease.

If you have any questions on the scientific content of this article, please call a Life Extension Wellness Specialist at 1-866-864-3027.

References

  1. Liu X, Guasch-Ferre M, Tobias DK, et al. Association of Walnut Consumption with Total and Cause-Specific Mortality and Life Expectancy in U.S. Adults. Nutrients. 2021 Aug 4;13(8).
  2. Available at: https://www.eurekalert.org/news-releases/925845. Accessed January 19, 2022.
  3. USDA. Nuts, walnuts, english. 2018.
  4. Guasch-Ferre M, Li J, Hu FB, et al. Effects of walnut consumption on blood lipids and other cardiovascular risk factors: an updated meta-analysis and systematic review of controlled trials. Am J Clin Nutr. 2018 Jul 1;108(1):174-87.
  5. Almario RU, Vonghavaravat V, Wong R, et al. Effects of walnut consumption on plasma fatty acids and lipoproteins in combined hyperlipidemia. Am J Clin Nutr. 2001 Jul;74(1):72-9.
  6. Mousavi SM, Shab-Bidar S, Kord-Varkaneh H, et al. Effect of alpha-lipoic acid supplementation on lipid profile: A systematic review and meta-analysis of controlled clinical trials. Nutrition. 2019 Mar;59:121-30.
  7. Xiao Y, Huang W, Peng C, et al. Effect of nut consumption on vascular endothelial function: A systematic review and meta-analysis of randomized controlled trials. Clin Nutr. 2018 Jun;37(3):831-9.
  8. Ma Y, Njike VY, Millet J, et al. Effects of walnut consumption on endothelial function in type 2 diabetic subjects: a randomized controlled crossover trial. Diabetes Care. 2010 Feb;33(2):227-32.
  9. Jalilpiran Y, Hajishafiee M, Khorshidi M, et al. The effect of Alpha-lipoic acid supplementation on endothelial function: A systematic review and meta-analysis. Phytother Res. 2020 Nov 18.
  10. Berryman CE, Grieger JA, West SG, et al. Acute consumption of walnuts and walnut components differentially affect postprandial lipemia, endothelial function, oxidative stress, and cholesterol efflux in humans with mild hypercholesterolemia. J Nutr. 2013 Jun;143(6):788-94.
  11. Haddad EH, Gaban-Chong N, Oda K, et al. Effect of a walnut meal on postprandial oxidative stress and antioxidants in healthy individuals. Nutr J. 2014 Jan 10;13:4.
  12. Kris-Etherton PM. Walnuts decrease risk of cardiovascular disease: a summary of efficacy and biologic mechanisms. J Nutr. 2014 Apr;144(4 Suppl):547S-54S.
  13. Tindall AM, Petersen KS, Skulas-Ray AC, et al. Replacing Saturated Fat With Walnuts or Vegetable Oils Improves Central Blood Pressure and Serum Lipids in Adults at Risk for Cardiovascular Disease: A Randomized Controlled-Feeding Trial. J Am Heart Assoc. 2019 May 7;8(9):e011512.
  14. Yang XY, Zhong DY, Wang GL, et al. Effect of Walnut Meal Peptides on Hyperlipidemia and Hepatic Lipid Metabolism in Rats Fed a High-Fat Diet. Nutrients. 2021 Apr 22;13(5).
  15. Bamberger C, Rossmeier A, Lechner K, et al. A Walnut-Enriched Diet Reduces Lipids in Healthy Caucasian Subjects, Independent of Recommended Macronutrient Replacement and Time Point of Consumption: a Prospective, Randomized, Controlled Trial. Nutrients. 2017 Oct 6;9(10).
  16. Rajaram S, Cofan M, Sala-Vila A, et al. Effects of Walnut Consumption for 2 Years on Lipoprotein Subclasses Among Healthy Elders: Findings From the WAHA Randomized Controlled Trial. Circulation. 2021 Sep 28;144(13):1083-5.
  17. Saedi E, Gheini MR, Faiz F, et al. Diabetes mellitus and cognitive impairments. World J Diabetes. 2016 Sep 15;7(17):412-22.
  18. Papadopoulou-Marketou N, Kanaka-Gantenbein C, Marketos N, et al. Biomarkers of diabetic nephropathy: A 2017 update. Crit Rev Clin Lab Sci. 2017 Aug;54(5):326-42.
  19. Tuccinardi D, Farr OM, Upadhyay J, et al. Mechanisms underlying the cardiometabolic protective effect of walnut consumption in obese people: A cross-over, randomized, double-blind, controlled inpatient physiology study. Diabetes Obes Metab. 2019 Sep;21(9):2086-95.
  20. Zibaeenezhad M, Aghasadeghi K, Hakimi H, et al. The Effect of Walnut Oil Consumption on Blood Sugar in Patients With Diabetes Mellitus Type 2. Int J Endocrinol Metab. 2016 Jul;14(3):e34889.
  21. Unuofin JO, Lebelo SL. Antioxidant Effects and Mechanisms of Medicinal Plants and Their Bioactive Compounds for the Prevention and Treatment of Type 2 Diabetes: An Updated Review. Oxid Med Cell Longev. 2020;2020:1356893.
  22. Jahanbani R, Ghaffari SM, Salami M, et al. Antioxidant and Anticancer Activities of Walnut (Juglans regia L.) Protein Hydrolysates Using Different Proteases. Plant Foods Hum Nutr. 2016 Dec;71(4):402-9.
  23. Catanzaro E, Greco G, Potenza L, et al. Natural Products to Fight Cancer: A Focus on Juglans regia. Toxins (Basel). 2018 Nov 14;10(11).
  24. Soriano-Hernandez AD, Madrigal-Perez DG, Galvan-Salazar HR, et al. The protective effect of peanut, walnut, and almond consumption on the development of breast cancer. Gynecol Obstet Invest. 2015;80(2):89-92.
  25. Poulose SM, Miller MG, Shukitt-Hale B. Role of walnuts in maintaining brain health with age. J Nutr. 2014 Apr;144(4 Suppl):561S-6S.
  26. Pandareesh MD, Chauhan V, Chauhan A. Walnut Supplementation in the Diet Reduces Oxidative Damage and Improves Antioxidant Status in Transgenic Mouse Model of Alzheimer's Disease. J Alzheimers Dis. 2018;64(4):1295-305.
  27. Muthaiyah B, Essa MM, Lee M, et al. Dietary supplementation of walnuts improves memory deficits and learning skills in transgenic mouse model of Alzheimer's disease. J Alzheimers Dis. 2014;42(4):1397-405.
  28. Chauhan A, Chauhan V. Beneficial Effects of Walnuts on Cognition and Brain Health. Nutrients. 2020 Feb 20;12(2).