benefits of walnuts

What’s New and Beneficial about Walnuts

Category : Food

Researchers are convinced – more than ever before – about the nutritional benefits of walnuts when consumed in whole form, including the skin. We now know that approximately 90% of the phenols in walnuts are found in the skin, including key phenolic acids, tannins, and flavonoids. Some websites will encourage you to remove the walnut skin – that whitish, sometimes waxy, sometimes flaky, outermost part of shelled walnuts. There can be slight bitterness to this skin, and that’s often the reason that websites give for removing it. However, we encourage you not to remove this phenol-rich portion.

The form of vitamin E found in walnuts is somewhat unusual, and particularly beneficial. Instead of having most of its vitamin E present in the alpha-tocopherol form, walnuts provide an unusually high level of vitamin E in the form of gamma-tocopherol. Particularly in studies on the cardiovascular health of men, this gamma-tocopherol form of vitamin E has been found to provide significant protection from heart problems. Most U.S. adults have yet to discover the benefits of walnuts. A recent study has determined that only 5.5% of all adults (ages 19-50) consume tree nuts of any kind! This small percentage of people actually do a pretty good job of integrating tree nuts (including walnuts) into their diet, and average about 1.25 ounces of tree nuts per day. But the other 94.5% of us report no consumption of tree nuts whatsoever. In a recent look at the nutritional differences between tree nut eaters and non-eaters, researchers have reported some pretty notable findings: on a daily average, tree nut eaters take in 5 grams more fiber, 260 milligrams more potassium, 73 more milligrams of calcium, 95 more milligrams of magnesium, 3.7 milligrams more vitamin E, and 157 milligrams less sodium.

Many of us can go local for our supply of walnuts. According to the latest trade statistics, 38% of all walnuts are grown in the U.S. Of that 38%, the vast majority (almost 90%) come from California, and particularly from the San Joaquin and Sacramento Valleys. Buying walnuts closer to home can provide great benefits from the standpoint of sustainability.

WH Foods Recommendations Walnuts are part of the tree nut family. This food family includes Brazil nuts, cashews, hazelnuts (filberts), macadamia nuts, pecans, pine nuts, pistachios and walnuts. It would be difficult to overestimate the potential health benefits associated with this food family! In the majority of dietary studies, approximately one ounce of tree nuts per day is the minimal amount needed to provide statistically significant benefits, and that’s the amount we recommend that you incorporate into your daily diet. In the case of walnuts, one ounce means about 7 shelled walnuts, or 14 walnut halves. Of course, since tree nuts (including walnuts) are a high-calorie food, it’s important to incorporate tree nuts into an overall healthy diet that remains on target in terms of calories. Luckily, research has shown that many people are able to take this step with good success in terms of overall caloric intake.

Walnuts not only taste great but are a rich source of heart-healthy monounsaturated fats and an excellent source of those hard to find omega-3 fatty acids. Like most nuts, they can easily be added to your Healthiest Way of Eating. Just chop and add to your favorite salad, vegetable dish, fruit, or dessert.

Health Benefits
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 inflammationregulating 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. 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

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 MetSrelated 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 midsection. Importantly, the MetS benefits of added walnuts have been achieved without causing weight gain in any the studies we’ve seen to date.