MCGC Nutrition

Walnuts: their health benefits

Marie-Claire Gahel-Calouche

Why talk about this often-forgotten nut? Among other benefits, a decrease in LDL cholesterol and triglycerides (TG), an improvement in diastolic pressure, a potential to protect against certain cancers, beneficial effects on the microbiome, which in turn demonstrate partial protection of cancer, in addition to being an excellent source of vegetable omega-3. In my expert opinion, these peculiarities make this food a better nutrient source than supplementation. Not only is this little gem an excellent source of omega-3, but it also has several nutrients that work together to allow a multitude of biomechanisms that offer an impressive range of health protection.


What explains such a range of protection? Let’s take a look at the scientific facts …

Eating nuts 5 times a week, regardless of the type, has shown a reduction in cardiovascular disease by 40%. Compared to a diet that is reduced in fat, a Mediterranean diet that includes mixed nuts had a 30% reduction in cardiovascular disease and a 49% reduction in the risk of a heart attack. Also, a plant-based diet, physical activity and achieving a healthy weight reduce the incidence of cancer by 30-40%. The

question, therefore, arises “If nuts, in general, demonstrate such efficiency, why speak of walnuts? The answer: the presence of polyphenols, omega-3 (ALA) and many antioxidants that have demonstrated beneficial and significant effects for cardiovascular health and the potential prevention of cancer. What’s more, their omega-3 and ˠ-tocopherol compositions are protective agents against cardiovascular disease, which makes walnuts a choice option for vegetarians who want nutritional benefits comparable to that of fatty fish in profile. lipid.


Let’s quantify benefits

Walnuts and cardiovascular disease:

Daily consumption of 42.5 g (about ⅓ cup without the shell) of walnuts has shown a reduction of 9% in LDL cholesterol and double this with a consumption of 84 g, and these increase the elimination of cholesterol LDL! When these nuts are consumed in a Mediterranean diet (37 g walnuts + 15g walnut oil) saw a decrease of 2-3 mmHg in diastolic pressure.

Walnuts and cancer:

Even more impressive, the research by Hardman et al. demonstrated 80% slower tumor growth among affected mice! In another mouse model, carrying genes for breast cancer or prostate cancer, only 40% of the mice developed a tumor versus 100% of the mice that were fed the alternative diet.

And how does the microbiome get into this story?

Another mechanism in protecting cancer is through the microbiome. Since the effects of a Mediterranean diet on the gut microbiome are known, Nakanishi et al. have shown that this effect can also be modulated by walnuts within a North American diet (Total Western Diet model) which also acts on the intestinal microbiome and offers partial protection against cancer.

How much should I consume to benefit?

According to the articles, 42.5 g (about ⅓ cup, equivalent to 5 portions of fat). If that sounds like a lot to you, remember that nutrition isn’t an all-or-nothing game. Every good deed towards health is important. So I simply recommend incorporating a few servings a day (e.g. a 1-1 ½ tablespoon serving of walnuts without the shell 2x a day as a snack).

Please note, this nut is delicate and should not be exposed to heat above 320oF. Have fun incorporating it, as good quality fat, into your favorite dishes and snacks. You can, therefore, use it in cold dishes (salads) as a garnish, on a fruit yogurt or simply by preparing a walnut pesto for a cold macaroni salad. Also, keep these nuts in a cold place, such as a freezer, to prevent them from becoming rancid. Before consuming them, smell them to ensure their freshness like any nut or seed.


Closing notes

I always encourage to eat as close to Mother Nature as possible: homemade and unprocessed foods. My reasons are simple: a quality whole food offers the concerted effects of their nutrients. The walnut is just one example among many. Every food choice is important and what we put on our plate has the potential to affect health. Indeed, why think only of “omega-3” when we can also think of the multitude of additional benefits that this food gives? I hope I have convinced you, at least of the importance of walnuts, and that before thinking about supplementation, think about the concerted effect of the nutrients in food and go to your grocery store. Your health and your wallet will thank you.

To your health!



  1. Zick SM, Wright BD, Sen A, Arnedt JT. Preliminary examination of the efficacy and safety of a standardized chamomile extract for chronic primary insomnia: a randomized placebo-controlled pilot study. BMC Complement Altern Med. 2011;11:78. Published 2011 Sep 22. doi:10.1186/1472-6882-11-78  
  2. Kelley DS, Adkins Y, Laugero KD. A Review of the Health Benefits of Cherries. Nutrients. 2018;10(3):368. Published 2018 Mar 17. doi:10.3390/nu10030368  
  3. Kwan, Live Science, 2021, Can drinking warm milk really help you fall asleep? Last accessed on 27 may 2022: 
  4. Jarry, McGill University, 2018, Chamomile Tea, Will You Help Me Sleep Tonight? Last accessed on 27 may 2022 :  
  5. Burkhardt S, Tan DX, Manchester LC, Hardeland R, Reiter RJ. Detection and quantification of the antioxidant melatonin in Montmorency and Balaton tart cherries (Prunus cerasus). J Agric Food Chem. 2001 Oct;49(10):4898-902. doi: 10.1021/jf010321+. PMID: 11600041.  
  6. Meng X, Li Y, Li S, et al. Dietary Sources and Bioactivities of Melatonin. Nutrients. 2017;9(4):367. Published 2017 Apr 7. doi:10.3390/nu9040367  
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