More Evidence That Nuts Are Good For You

Cardiovascular disease was inhibited to a greater degree by a Mediterranean diet supplemented by olive oil or nuts compared to a control low fat diet.  Abstract:

Background Observational cohort studies and a secondary prevention trial have shown inverse associations between adherence to the Mediterranean diet and cardiovascular risk. Methods In a multicenter trial in Spain, we assigned 7447 participants (55 to 80 years of age, 57% women) who were at high cardiovascular risk, but with no cardiovascular disease at enrollment, to one of three diets: a Mediterranean diet supplemented with extra-virgin olive oil, a Mediterranean diet supplemented with mixed nuts, or a control diet (advice to reduce dietary fat). Participants received quarterly educational sessions and, depending on group assignment, free provision of extra-virgin olive oil, mixed nuts, or small nonfood gifts. The primary end point was a major cardiovascular event (myocardial infarction, stroke, or death from cardiovascular causes). After a median follow-up of 4.8 years, the trial was stopped on the basis of a prespecified interim analysis. In 2013, we reported the results for the primary end point in the Journal. We subsequently identified protocol deviations, including enrollment of household members without randomization, assignment to a study group without randomization of some participants at 1 of 11 study sites, and apparent inconsistent use of randomization tables at another site. We have withdrawn our previously published report and now report revised effect estimates based on analyses that do not rely exclusively on the assumption that all the participants were randomly assigned. Results A primary end-point event occurred in 288 participants; there were 96 events in the group assigned to a Mediterranean diet with extra-virgin olive oil (3.8%), 83 in the group assigned to a Mediterranean diet with nuts (3.4%), and 109 in the control group (4.4%). In the intention-to-treat analysis including all the participants and adjusting for baseline characteristics and propensity scores, the hazard ratio was 0.69 (95% confidence interval [CI], 0.53 to 0.91) for a Mediterranean diet with extra-virgin olive oil and 0.72 (95% CI, 0.54 to 0.95) for a Mediterranean diet with nuts, as compared with the control diet. Results were similar after the omission of 1588 participants whose study-group assignments were known or suspected to have departed from the protocol. Conclusions In this study involving persons at high cardiovascular risk, the incidence of major cardiovascular events was lower among those assigned to a Mediterranean diet supplemented with extra-virgin olive oil or nuts than among those assigned to a reduced-fat diet. (Funded by Instituto de Salud Carlos III, Spanish Ministry of Health, and others; Current Controlled Trials number, ISRCTN35739639 .).

Nut Intake Equals Reduced Weight Gain

By Sage Ross - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=30392736

Nut intake is associated with “reduced weight gain and a lower risk of becoming overweight or obese.”  So, in moderation, eating a healthy “energy-dense food” like nuts can be beneficial for weight control.  Don’t over-indulge of course, but it would seem like a handful of nuts is better than a handful of doughnuts.  Abstract:

PURPOSE:There is inconsistent evidence regarding the relationship between higher intake of nuts, being an energy-dense food, and weight gain. We investigated the relationship between nut intake and changes in weight over 5 years.METHODS:This study includes 373,293 men and women, 25-70 years old, recruited between 1992 and 2000 from 10 European countries in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Habitual intake of nuts including peanuts, together defined as nut intake, was estimated from country-specific validated dietary questionnaires. Body weight was measured at recruitment and self-reported 5 years later. The association between nut intake and body weight change was estimated using multilevel mixed linear regression models with center/country as random effect and nut intake and relevant confounders as fixed effects. The relative risk (RR) of becoming overweight or obese after 5 years was investigated using multivariate Poisson regressions stratified according to baseline body mass index (BMI).RESULTS:On average, study participants gained 2.1 kg (SD 5.0 kg) over 5 years. Compared to non-consumers, subjects in the highest quartile of nut intake had less weight gain over 5 years (-0.07 kg; 95% CI -0.12 to -0.02) (P trend = 0.025) and had 5% lower risk of becoming overweight (RR 0.95; 95% CI 0.92-0.98) or obese (RR 0.95; 95% CI 0.90-0.99) (both P trend <0.008).CONCLUSIONS:Higher intake of nuts is associated with reduced weight gain and a lower risk of becoming overweight or obese.

Dried Fruit And Nuts For Type 2 Diabetes

Figure 1

Role of nutrients from nuts and dried fruits in glucose and insulin metabolism, and cellular and molecular mechanisms related to T2D/IR. CHO, carbohydrate; CMF, cellular membrane fluidity; GI, glycaemic index; IR, insulin resistance; MUFA, monounsaturated fatty acid; PUFA, polyunsaturated fatty acid; T2D, type 2 diabetes. http://www.mdpi.com/2072-6643/9/7/673/htm (Figure from the open access paper)

Of course, diabetics need to follow the instructions of their physicians; however, we present this article for readers' interest.  It suggests that eating nuts and dried fruit (DF) can be beneficial for diabetics; some of the possible mechanisms are outlined in the figure (above) from the paper.  The fiber and relatively low glycemic index, healthy fats, minerals, and various bioactive compounds alter gene expression, microRNAs (RNA that control gene expression), and microbiota and so helpfully "modulate glucose and insulin metabolism." From the conclusion:

Undoubtedly, the specific composition of nuts and dried fruits means that they can be used to efficiently counteract metabolic diseases such as type 2 diabetes. Their unique profile of macronutrients, micronutrients and other bioactive compounds may explain the beneficial effects observed in clinical and epidemiological studies. However, the exact mechanisms by which they modulate glucose and insulin metabolism and influence T2D have yet to be fully discovered. They contain fiber, fat, minerals and other bioactive molecules that modulate several gene mechanisms at the cellular and molecular level. This may explain some of their beneficial effects. However, further basic and translational research is needed in order to extend their positive health benefits and to find novel mechanisms and targets to explain their contribution to the management of type 2 diabetes.

What about the sugars in the dried fruit?  The authors claim:

Carbohydrate Content—Glycaemic Index of Nuts and Dried Fruits

It should be noted that nuts are relatively low in CHO (approximately 15% of the total energy) whereas DFs have a high amount of CHO (60–80%). Nuts have a low glycaemic index and therefore increase the blood glucose level less and require less insulin secretion, thus favoring the control of T2D. However, because DFs are high in carbohydrates and fiber, their specific GI has been the object of considerable study. The GI of raisins was first evaluated in three heterogeneous groups of subjects (aerobically trained, sedentary or pre-diabetic) and was described between 49 and 69, therefore corresponding to the low-to-moderate GI foods [110]. However, later studies have reported that raisins are in the low GI category in healthy subjects (a GI of 49.4 and an insulinemic index of 47.1) [15]. This suggests a favorable postprandial glucose and insulin response [112], that could be explained by the high proportion of fructose that DFs contain.

Overall, the inclusion of both nuts and DFs in a balanced diet may reduce the overall glycaemic index of the diet, with benefits to glycaemic and insulinemic control in both healthy and T2D subjects.

Fructose of course can cause problems but when combined with the high fiber in the dried fruits that is obviated.

Going Nuts for Heart Health

When I was young, the paradigm was ‘fat is fat”, and all forms of fat were to be reduced to the absolute minimum. That led to a carbohydrates - heavy diet which likely has contributed to today’s epidemic of obesity, metabolic syndrome, and type 2 diabetes. Today, our current understanding is that unsaturated fats, in moderation, can be healthy. Thus, nuts, one forbidden as a “fat food,” are now considered healthy, if consumed in moderation, and as part of an overall healthy diet.
 

Eating nuts as part of a healthy diet can be good for your heart. Nuts, which contain unsaturated fatty acids and other nutrients, are a great snack food, too. They're inexpensive, easy to store and easy to pack when you're on the go.
 
The type of nut you eat isn't that important, although some nuts have more heart-healthy nutrients and fats than do others. Walnuts, almonds, hazelnuts — you name it — almost every type of nut has a lot of nutrition packed into a tiny package. If you have heart disease, eating nuts instead of a less healthy snack can help you more easily follow a heart-healthy diet.
 
Can eating nuts help your heart?
 
People who eat nuts as part of a heart-healthy diet can lower the low-density lipoprotein (LDL, or "bad") cholesterol level in their blood. High LDL is one of the primary causes of heart disease.
 
Eating nuts may reduce your risk of developing blood clots that can cause a fatal heart attack.
 

Once again, moderation is key.

 As much as 80 percent of a nut is fat. Even though most of this fat is healthy fat, it's still a lot of calories. That's why you should eat nuts in moderation. Ideally, you should use nuts as a substitute for saturated fats, such as those found in meats, eggs and dairy products. 

Instead of eating unhealthy saturated fats, try substituting these with a handful of nuts or a tablespoon or two of a nut spread. The American Heart Association recommends eating four servings of unsalted nuts a week. Select raw or dry-roasted nuts rather than those cooked in oil.

A serving is a small handful (1.5 ounces) of whole nuts or 2 tablespoons of nut butter. But again, do this as part of a heart-healthy diet. Just eating nuts and not cutting back on saturated fats found in many dairy and meat products won't do your heart any good.

Eating some walnut or almonds, or having a couple of tablespoons of peanut butter or almond butter can therefore constitutes a tasty part of a heart-healthy diet.

Check these recipes for walnut-chocolate clusters and spicy walnuts.