I consider myself an amateur when it comes to nuts, I asked passing customers which one was best and why. The responses were as variable as the people. One man said, “You are a man and one is for men’s health, so you should choose that one.” I asked why it might help me as a man, and he said because it was a great source of fiber. (Looking back, I’m not sure it’s ever a good idea to rely on a guy in a grocery store to recommend that you take more fiber.) Another shopper recommended the heart-healthy mix. When I asked why, she said because it has more walnuts and pistachios and they are good for the heart. My experiment seemed to fizzle when an authoritative elderly man joined the discussion. He said we were all wrong and that only raw nuts were healthy. He was not amused when I asked if he thought it was okay if I met my daily nut needs by eating a candy bar.
A Heart-Healthy Passion for Nuts
I learned a few things about nuts and people. First, some people are very passionate about their nuts. Also, people seem to feel peanuts are the least healthy nuts and perceive them as degrading a mixed-nut selection. What I thought was good news is that most people recognized that the nuts were often salted and felt healthy mixes should have less salt or no salt. The bottom line, based on the research evidence, is that all nuts are a very healthy choice. Many new clinical studies highlight heart-related benefits of nuts. For example, adding 30 grams (gm) per day of nuts a little over an ounce) to a Mediterranean diet lowers risk of heart disease by 30 percent Based on the research, here’s a breakdown of the links betweeen nuts and heart disease, and what makes nuts heart healthy. I hope this will help you make tough choices, such as which nut mix to purchase.
Almonds Help Lower Cholesterol and Body Fat
Adding almonds to your diet lowers your LDL cholesterol, or bad cholesterol, which is involved in creating plaques in your coronary arteries that can cause heart attacks. Almonds lower LDL in a dose-dependent manner. This means that by increasing the amount of almonds you eat, you can further lower your LDL. Clinical diet studies show almonds can also reduce your risk of insulin resistance and diabetes. Even if you have diabetes, adding almonds to your diet can improve your sensitivity to insulin. Almonds can also increase your likelihood of losing weight. In one study, adding 84 gm, or about 3 ounces (oz) of almonds a day to a planned diet improved weight loss and resulted in a 14 percent decrease in waist circumference. A study published in 2015 looked at cholesterol and body fat in people who ate 1.5 oz of almonds a day versus a healthy muffin with similar calories. In only six weeks, people who consumed almonds had lower LDL cholesterol by an average of 5 mg/dL. They also had less belly fat and leg fat. There are also several studies showing eating almonds lowers body inflammation. If you are looking to shrink your waist and improve your cholesterol, start by adding some almonds to your diet.
Pistachios Help Lower Blood Pressure Under Stress
Adding pistachios to your diet also has potential heart benefits. Previously, I discussed how our body and heart responds adversely to stress and how we respond to it with increased blood pressure. A study of people who ate approximately 1.5 0z of pistachios a day and were then exposed to mental stress found they had lower blood pressure rises than those who did not eat pistachios. In people with diabetes, eating pistachios lowers total and LDL cholesterol and can reduce the risk of diabetes-related disease in the arteries. In a four-week trial published in 2014 of patients who had diabetes, a diet rich in pistachios (about 6 to 10 gm/day) improved heart rate response to stress, 24-hour blood pressure measurements, and heart function and output. Total cholesterol also decreased for those who ate pistachios. If you are looking to lower your blood pressure, improve your response to stress, and lower your cholesterol, consider adding pistachios to your diet.
Walnuts Help Keep Arteries Clear
Most nuts contain a high concentration of healthy fat. Walnuts are composed of 47 percent polyunsaturated fatty acids, thought of as “good fats.” But while most nuts contain polyunsaturated fatty acids, walnuts are the only ones with a significant amount of a certain type called alpha-linoleic acid. Alpha-linoleic acid acts as an anti-inflammatory agent and has actually been shown to help reduce plaque buildup in coronary arteries. Eating walnuts has been shown to improve cholesterol levels and the function of the small arteries and vessels within our bodies. Recently, a study looking people who consumed 43 gm of walnuts every day found the nuts reduced total and LDL cholesterol levels. However this study showed something even more important, in my view. Consumption of walnuts reduced the level of apolipoprotein B, which is a strong genetic risk factor for coronary artery disease. If you are at high risk for coronary artery disease (CAD) or already have it, consider adding walnuts to your diet.
The Truth About Peanuts
In my grocery store experiment, peanuts took a beating. However, many studies show eating peanuts, including peanut butter, can reduce heart risk. In the Nurse’s Health Study, those women who consumed peanuts and peanut butter lowered their risk of heart disease by 34 percent. The greatest benefit was in those who ate peanuts multiple times a week. In a study of 6,309 women with diabetes, eating one serving of peanuts (28 gm [1 oz] for nuts and 16 gm [1 tablespoon] for peanut butter) five times a week or more lowered risk of heart disease by 44 percent. Eating peanuts and peanut butter has also been shown to lower risk of diabetes in both lean and overweight women. Finally, like many other nuts, peanuts as an alternative food source for your protein needs can lower your cholesterol, particularly when added to other healthy diet choices. If you are like the people in my study, perhaps you are asking: Are peanuts better than the others I have mentioned? A recent study looked at this question, specifically diets rich in peanuts versus tree nuts. This study shed some light on the potential greater benefit of tree nuts compared to peanuts. In 803 adults, abdominal obesity, blood pressure, and cholesterol where all better controlled in those who had a high intake of tree nuts. However, if you ate a lot of tree nuts, it didn’t seem to matter how many peanuts you ate. Like the other trials mentioned in this section, this one showed that eating peanuts was better than not eating nuts, peanuts or other nuts, in regard to better blood pressure and cholesterol levels. The most striking difference in the study was that high consumption of tree nuts did not increase risk of abdominal obesity, whereas high consumption of peanuts alone did.
Can You Eat too Many Nuts?
The answer is yes, absolutely. The best approach to eating nuts is moderation. Nuts are very good sources of energy, and if you eat too much you can gain weight and offset the heart benefits. I like to recommend adding nuts to an already heart-healthy diet or as an alternative healthy snack. If you change your snacks alone to unsalted nuts you will be surprised how effective that choice is in helping with weight loss and cholesterol management. One thing to keep in mind is that some people can experience dangerous allergic reactions to nuts. If you have a potential allergy or a family history of nut allergies, don’t consider using nuts until you talk with your doctor. Finally, there are data regarding contamination of some nuts with mycotoxins. Consider reading about these toxins as I don’t have enough room to cover them here. The one that has the most data behind it is cases of contamination of peanuts with aflatoxin.
An Apology to Pecan, Hazelnut, and Macadamia Fans
I want to apologize for the nuts left off this list. It was not intentional. Pecans, hazelnuts, and macadamia nuts have also shown some benefits in reducing heart disease factors, but they don’t have the data of the nuts listed above. I hope this information will help you with your next nut purchase or your next spirited debate with a passionate nut person. T. Jared Bunch, MD is a native of Logan Utah and directs heart rhythm research at the Intermountain Medical Center Heart Institute. You can follow @TJaredBunch on Twitter.
