Juglans regia / Walnootboom

Health Benefits of Juglans regia

Cardiovascular Benefits

No aspect of walnuts has been better evaluated in the research than their benefits for the heart and circulatory system. Some review studies have emphasized the very favorable impact of walnuts on "vascular reactivity," namely, the ability of our blood vessels to respond to various stimuli in a healthy manner. In order to respond to different stimuli in a healthy way, many aspects of our cardiovascular system must be functioning optimally. These aspects include: ample presence of antioxidant and anti-inflammatory nutrients, proper blood composition, correct balance in inflammation-regulating molecules, and proper composition and flexibility in our blood vessel walls. Researchers have determined the ability of walnuts to have a favorable impact on all of these aspects. The chart below summarizes some key research findings about walnuts and heart health:

Cardiovascular Aspect Walnut Benefit

Blood Quality: decreased LDL cholesterol; decreased total cholesterol; increased gamma-tocopherol; increased omega-3 fatty acids in red blood cells (alpha-linolenic acid)

Vasomotor Tone: decreased aortic endothelin; improved endothelial cell function

Risk of Excessive Clotting: decreased maximum platelet aggregation rate; decreased platelet activation

Risk of Excessive Inflammation: decreased C reactive protein (CRP); decreased tumor necrosis factor alpha (TNF-a)

Research on the blood pressure benefits of walnuts has been mixed. We suspect that these mixed results are related to the surprising differences in mineral composition amongst different varieties of walnuts. Researchers have long been aware of the relationship between healthy blood pressure and intake of specific minerals, including potassium, calcium, and magnesium. In multiple studies, these minerals have a much greater impact on blood pressure than the mineral sodium (familiar to most people in its sodium chloride form, i.e., everyday table salt). We've seen studies showing the following ranges for key blood pressure-regulating minerals in walnuts:

Mineral Natural Range Found Amongst Different Walnut Varieties (milligrams per 100 grams)

    • Potassium 375-500

    • Calcium 13-91

    • Magnesium 189-278

Even though there are valuable amounts of these blood pressure-regulating minerals in virtually all varieties of walnuts, the ranges above may help explain why some studies have shown statistically significant benefits from walnuts on blood pressure while others have not.

Not in question with respect to walnuts and cardiovascular support is their reliable omega-3 content. Adequate intake of omega-3s, including the alpha-linolenic acid (ALA) present in walnuts, has repeatedly been shown to help improve a wide variety of cardiovascular functions, including blood pressure. In at least one research study, adults have been able to significantly increase their blood level of ALA with as few as 4 walnuts per day.

Walnuts Help Reduce Problems in Metabolic Syndrome

In the United States, as many as 1 in 4 adults may be eligible for diagnosis with Metabolic Syndrome (MetS). MetS isn't so much a "disease" as a constellation of problematic and overlapping metabolic problems including excessive blood fats (triglycerides), high blood pressure, inadequate HDL cholesterol, and obesity (as measured by waist circumference, and/or body mass index). Recent studies have shown that approximately one ounce of walnuts daily over a period of 2-3 months can help reduce several of these MetS-related problems. In addition, addition of walnuts to participant diets has also been shown to decrease "abdominal adiposity"—the technical term for the depositing of fat around the mid-section. Importantly, the MetS benefits of added walnuts have been achieved without causing weight gain in any the studies we've seen to date.

Benefits in Treatment of Type 2 Diabetes

Although we think about type 2 diabetes as a problem primarily related to blood sugar control and insulin metabolism, persons diagnosed with type 2 diabetes typically have health problems in other related systems, and are at special risk for cardiovascular problems. An important part of the goal in designing a diet plan for persons with type 2 diabetes is lowering the risk of future cardiovascular problems. In this context, consumption of walnuts is establishing a more and more impressive research track record. Increased flexibility in the response of the cardiovascular system following meals has been a repeated finding in research on walnuts. A variety of different measurements on blood vessel functioning (including their measurement by ultrasound) show a relatively small amount of daily walnut intake (1-2 ounces) to provide significant benefits in this area for persons with type 2 diabetes. Better blood fat composition (including less LDL cholesterol and less total cholesterol) has also been demonstrated in persons with type 2 diabetes.

Anti-Cancer Benefits

Given the wide variety antioxidant and anti-inflammatory nutrients found in walnuts, it's not surprising to see research on this tree nut showing measurable anti-cancer benefits. The antioxidant properties of walnuts help lower risk of chronic oxidative stress, and the anti-inflammatory properties help lower risk of chronic inflammation, and it is precisely these two types of risk, that, when combined, pose the greatest threat for cancer development. Prostate cancer and breast cancer are the best-studied types of cancer with respect to walnut intake, and their risk has been found to be reduced by fairly large amounts of walnut consumption. (Large in this case means approximately 3 ounces per day.) For prostate cancer, the evidence is somewhat stronger, and more studies have involved human subjects. For breast cancer, most of the evidence has been based on studies of rats and mice.

Other Health Benefits

The anti-inflammatory nutrients in walnuts may play a special role in support of bone health. A recent study has shown that large amounts of walnuts decrease blood levels of N-telopeptides of type 1 collagen (NTx). These collagen components provide a good indicator of bone turnover, and their decreased blood level in response to walnut intake is an indication of better bone stability and less mineral loss from the bone. "Large amounts" of walnuts (in this study, actually raw walnuts plus walnut oil) translated into 50% of total dietary fat. In an everyday diet that provided 2,000 calories and 30% of those calories from fat, this 50% standard for walnuts would mean about 67 grams of fat from walnuts or 4 ounces of this tree nut on a daily basis. While this amount is more than would most people would ordinarily consume, we expect the health benefits of walnuts for bone health to be demonstrated in future studies at substantially lower levels of intake.

Walnuts have also produced a good track record in the research as a desirable food for support of weight loss and for prevention of obesity. That finding often surprises people because they think of high-fat, high-calorie foods as a primary contributing factor to obesity and to weight gain. In general, overconsumption of high-fat, high-calorie foods is a primary contributing factor to obesity and weight gain. However, obesity has also been clearly identified by researchers as involving chronic, unwanted inflammation. As discussed earlier in this Health Benefits section and throughout this walnuts' profile, walnuts are unique in their collection of anti-inflammatory nutrients. These nutrients include omega-3 fatty acids; phytonutrients including tannins, phenolic acids, and flavonoids; quinones like juglone; and other anti-inflammatory phytonutrients. These anti-inflammatory benefits can overshadow the high-calorie and high-fat risk posed by walnuts, and that's exactly what they have done in an increasing number of research studies involving risk and/or treatment of obesity. While it is definitely possible to overconsume walnuts, most everyday diets could remain correctly balanced in terms of calories and fat while still including fairly generous amounts of walnuts (in the range of 1-3 ounces).

A limited (but increasing) number of studies have shown potential health benefits for walnuts in the area of memory and general thought processes (often referred to as "cognitive" processes). Thus far, most of the initial research in this area has involved rats and mice, but we expect to see cognitive benefits of walnuts for humans becoming a topic of increasing research interest.

A final fascinating aspect of walnuts and their potential health benefits involves melatonin (MLT). MLT is a widely-active messaging molecule in our nervous system, and very hormone-like in its regulatory properties. MLT is critical in the regulation of sleep, daily (circadian) rhythms, light-dark adjustment, and other processes. It has also been found to be naturally occurring within walnuts. Average melatonin (MLT) content of walnuts is approximately 3.6 nanograms (ng) per gram (g), or 102ng/ounce. Other commonly eaten foods - for example, cherries - have also been found to measurable amounts of MLT. Researchers are not yet sure how everyday intake of MLT from walnuts is involved in our health, but several study authors have hypothesized about the MLT in walnuts as playing an important role (along with other walnut nutrients) in the anti-cancer benefits of this unusual food.

References

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    • Bes-Rastrollo M, Sabate J, Gomez-Gracia E, Alonso A, Martinez JA, Martinez-Gonzalez MA. Nut consumption and weight gain in a Mediterranean cohort: The SUN study. Obesity (Silver Spring). 2007 Jan;15(1):107-16. 2007. PMID:17228038.

    • Blomhoff R, Carlsen MH, Andersen LF, Jacobs DR Jr. Health benefits of nuts: potential role of antioxidants. Br J Nutr. 2006 Nov;96 Suppl 2:S52-60. 2006. PMID:17125534.

    • Cortes B, Nunez I, Cofan M, Gilabert R, Perez-Heras A, Casals E, Deulofeu R, Ros E. Acute effects of high-fat meals enriched with walnuts or olive oil on postprandial endothelial function. J Am Coll Cardiol. 2006 Oct 17;48(8):1666-71. 2006. PMID:17045905.

    • Ensminger AH, Ensminger, ME, Kondale JE, Robson JRK. Foods & Nutriton Encyclopedia. Pegus Press, Clovis, California. 1983.

    • Ensminger AH, Esminger M. K. J. e. al. Food for Health: A Nutrition Encyclopedia. Clovis, California: Pegus Press; 1986. 1986. PMID:15210.

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    • Fukuda T, Ito H, Yoshida T. Antioxidative polyphenols from walnuts (Juglans regia L.). Phytochemistry. Aug;63(7):795-801. 2003.

    • Gillen LJ, Tapsell LC, Patch CS, Owen A, Batterham M. Structured dietary advice incorporating walnuts achieves optimal fat and energy balance in patients with type 2 diabetes mellitus. J Am Diet Assoc. 2005 Jul;105(7):1087-96. 2005. PMID:15983525.

    • Griel AE, Kris-Etherton PM, Hilpert KF, Zhao G, West SG, Corwin RL. An increase in dietary n-3 fatty acids decreases a marker of bone resorption in humans. Nutr J. 2007 Jan 16;6:2. 2007. PMID:17227589.

    • Kelly JH Jr, Sabate J. Nuts and coronary heart disease: an epidemiological perspective. Br J Nutr. 2006 Nov;96 Suppl 2:S61-7. 2006. PMID:17125535.

    • Marangoni F, Colombo C, Martiello A, Poli A, Paoletti R, Galli C. Levels of the n-3 fatty acid eicosapentaenoic acid in addition to those of alpha linolenic acid are significantly raised in blood lipids by the intake of four walnuts a day in humans. Nutr Metab Cardiovasc Dis. 2006 Sep 25; [Epub ahead of print] . 2006. PMID:17008073.

    • Morgan JM, Horton K, Reese D et al. Effects of walnut consumption as part of a low-fat, low-cholesterol diet on serum cardiovascular risk factors. Int J Vitam Nutr Res 2002 Oct; 72(5):341-7. 2002.

    • Patel G. Essential fats in walnuts are good for the heart and diabetes. J Am Diet Assoc. 2005 Jul;105(7):1096-7. 2005. PMID:15983525.

    • Reiter RJ, Manchester LC, Tan DX. Melatonin in walnuts: influence on levels of melatonin and total antioxidant capacity of blood. Nutrition. 2005 Sep;21(9):920-4. 2005. PMID:15979282.

    • Ros E, Nunez I, Perez-Heras A, Serra M, Gilabert R, Casals E, Deulofeu R. A walnut diet improves endothelial function in hypercholesterolemic subjects: a randomized crossover trial. Circulation. 2004 Apr 6;109(13):1609-14. 2004. PMID:15037535.

    • Stevens LJ, Zentall SS, Abate ML, et al. Omega-3 Fatty Acids in Boys with Behavior, Learning, and Health Problems. Physiol Behav 59(4/5) 915-920. 1996. 1996.

    • Stevens LJ, Zentall SS, Deck JL, et al. Essential Fatty Acid Metabolism in Boys with Attention-Deficit Hyperactivity Disorder. American Journal of Clinical Nutrition, 1995 Oct; 62(4): 761-8. 1995.

    • Tapsell LC, Gillen LJ, Patch CS, Batterham M, Owen A, Bare M, Kennedy M. Including Walnuts in a Low-Fat/Modified-Fat Diet Improves HDL Cholesterol-to-Total Cholesterol Ratios in Patients With Type 2 Diabetes. Diabetes Care. 2004 Dec;27(12):2777-83. 2004. PMID:15562184.

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    • Ueshima H, Stamler J, Elliott P, Chan Q, Brown IJ, Carnethon MR, Daviglus ML, He K, Moag-Stahlberg A, Rodriguez BL, Steffen LM, Van Horn L, Yarnell J, Zhou B. Food Omega-3 Fatty Acid Intake of Individuals (Total, Linolenic Acid, Long-Chain) and Their Blood Pressure. INTERMAP Study. Hypertension. 2007 Jun 4; [Epub ahead of print] . 2007. PMID:17548718.

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    • Zhao G, Etherton TD, Martin KR, West SG, Gillies PJ, Kris-Etherton PM. Dietary {alpha}-Linolenic Acid Reduces Inflammatory and Lipid Cardiovascular Risk Factors in Hypercholesterolemic Men and Women. J Nutr. 2004 Nov;134(11):2991-2997. 2004. PMID:15514264.

[784] Die Noteboomen worden seer hooch ende dick/ ende crijghen veel tacken die huer veerde ende wijt uutbreyden/ uut den welcken in dat ierste van der lenten voortcomen langhe bleeckgeele cattekens/ schier ghelijck aen die Wilghen maer langhere/ die huer selven ontpluycken ende corts daer naer afvallen. Ende daer naer zoo comen die bladeren voort/ die lanck groot ende welrieckende sijn/ van vele bladeren aen een ribbeken tseghen malcanderen over wassende vergaert/ van den welcken elck besondere oock groot ende breet es. Die vruchten wassen tusschen die bladeren/ twee drye oft vier tsamen ende elck es met een groene snoestere bedeckt/ daer onder een herde houtachtighe scelpe es/ daer die keerne tusschen vellekens in besloten leyt.

Dodonaeus Cruijdeboeck 1554 deel 6 capitel 55, bladzijde 783-784 Van Noteboom. Cap. lv.

Carya, Nux, Noteboom

(vrucht) Caryon basilicon, Nux regia, Nux iuglans, Nux Persica (Nux), Okernoot, Okernoten, Noot, Noten (katjes, "ionghe Catekens") Iuli nucum

1644 Vlaams: Nooteboom, Nootelaer, Okernotenboom (vrucht: Okernoten, Walsche noten)

1616 Latijn: Nux iuglans (vrucht: Nux, Nux Iuglans, Nux regia) [816]

1554/1557: Baumnusz, Gauguier, Iuli nucum, Noix, Noteboom, Noyer, Nuszbaum, Nux, Nux iuglans, Nux Persica, Nux regia, Okernoten, Welschnusz

Plaetse

Noteboomen groeyen geerne op bergachtighe ende drooghe plaetsen/ ende worden hier te lande/ ende in Duytschlant in veel hoven/ ende aen die canten van den velden gheplant.

Tijt

Die cattekens van den Noteboom beghinnen uut te comen in Meerte/ oft ten lancxsten in Aprill. Die Noten worden rijp ontrent dat eynde van Oostmaent.

Naem

Die Noteboom wordt gheheeten in Griecx Carya/ In Latijn Nux/ In Hoochduytsch Nuszbaum/ In Franchois ung Noissier.

Die ionghe Cattekens die voor die bladeren uutcomen/ worden gheheeten in Latijn Iuli nucum.

Die vrucht es ghenaemt in Griecx Caryon basilicon/ In Latijn Nux regia, Nux iuglans, en Nux Persica/ In die Apoteken Nux/ In Hoochduytsch Welschnusz und Baumnusz. Hier te lande Okernoten/ In Franchois ung Noix.

Natuere

Noten noch groen ende versch/ sijn cout ende vochtich.

Die drooghe Noten sijn werm/ verdrooghende ende subtijl van substantien.

Die snoesteren van den Noten verdrooghen seer ende sijn tsamen treckende van natueren/ ende van ghelijcke natuere sijn oock volnaer die bladeren.

Cracht ende werckinghe

A Die gruene ende versche Noten sijn bequaemer om eten/ dan die drooghe/ nochtans zoo sijn sy quaet om te verteeren ende voeden seer luttel.

B Die drooghe Noten voeden veel min ende sijn quaeder om verteeren/ sy maken hooftsweer/ ende sijn quaet voor die maghe/ ende den ghenen die hoesten ende cort van adem sijn.

C Een oft twee drooghe Noten met een Vijghe ende wat Ruyten inghenomen smorghens nuchtere sijn seer goet tseghen alle fenijn.

D Item drooghe Noten met sout/ huenich/ en aijeuijn vermenght/ sijn goet gheleyt op die beten van den verwoeden honden. Ende met huenich ende wat Ruyten alleen ghemenght/ zoo ghenesen sy oock die sweeringhen van den borsten/ ende andere coude apostumatien.

E Die verouderde vette Noten ghenesen die quade scorftheden van den hoofde/ ende doen vergaen die blauwe gheslaghen ende ghestooten plecken/ cleyn ghestooten ende daer op gheleyt. Tselve doet oock die Olie uut den Noten gheperst.

F Van den snoesteren van den Noten/ wordt een medecijne gemaeckt die tot alle swillinghen ende ierst groeyende sweeringhen van der keelen/ amandelen/ ende van den mont seer goet es/ alsmen daer mede gorgelt.

G Tot den selven ghebreken dienen oock die snoesteren in water ghesoden ende daer mede gegorgelt. Ende van ghelijcke cracht sijn oock schier die bladeren.

Walnuts Can Help You Beat Stress

Margie King, Health Coach

If you're feeling stressed out or you know that you're in for a bad day, you might want to eat a handful of walnuts to relieve the pressure. According to one study by researchers at Penn State University, a diet rich in walnuts and walnut oil may prepare the body to deal better with stress.

The researchers wanted to examine how walnuts and walnut oil, which contain polyunsaturated fats, influence blood pressure at rest and under stress. That's because people who have an exaggerated biological response to stress are at higher risk of heart disease. According to the researchers, they wanted to find out if omega 3-fatty acids from plant sources would blunt cardiovascular responses to stress.

In the study 22 healthy adults with elevated LDL cholesterol followed three different diets for six weeks each. The participants were subjected to stress either by giving a speech or immersing a foot in cold water. The results, published in the Journal of the American College of Nutrition, showed that when participants were following a diet that included walnuts and walnut oil, their blood pressure and stress responses were lower.

The "average" American diet does not include any nuts on a daily basis and the diet found to be effective to reduce the stress reaction included about 9 whole walnuts as an average serving. That may be all it takes for you to feel the calming effects.

A quarter cup of walnuts provides over 90% of the recommended daily value of omega-3 fats. Previous studies had already shown that omega-3 fatty acids like the alpha linolenic acid found in walnuts and flax seeds, can reduce LDL (the so-called bad) cholesterol, and may also reduce inflammation.

Walnuts are rich in healthy fats, dietary fiber, minerals, vitamins, antioxidants and phytosterols, and have long been associated with heart health. The U.S. Food and Drug Administration allows walnut providers to make the health claim that "eating 1.5 ounces per day of walnuts as part of a diet low in saturated fat and cholesterol may reduce the risk of heart disease."

Besides its beneficial effects on blood pressure and inflammation, walnuts have also been shown to be an excellent source of antioxidants, help to prevent gallstones, improve sleep by boosting melatonin, protect bone health and prevent weight gain.

Now this study points out that walnuts and walnut oil reduce blood pressure during stressful periods. And since we can't completely avoid all the stresses in our lives, it's good to know that such a simple and convenient snack could help us deal with the pressure.