By Dr. Mercola
If you're looking for a nutritious, quick snack, nuts (raw, organic and in moderation) are a near perfect option.
With healthy fats, fiber, plant sterols and many vitamins and minerals, nuts pack a powerful nutritional punch, all wrapped up in a tiny bite-sized package.
In fact, a recent epidemiologic study revealed that nuts offer many benefits for your health, even reducing your risk of serious chronic disease.
Nuts Support Heart Health, Lower Diabetes, Metabolic Syndrome Risk
There have not been many epidemiologic studies undertaken to assess the effect of nut consumption on health risks, but a recent study involving more than 13,000 people, published in the Journal of the American College of Nutrition, set out to do just that.
Those who ate nuts gained numerous benefits compared to non-nut eaters, including:
- Decreased body mass index and waist circumference
- Lower systolic blood pressure
- Lower weight
- Less likelihood of having two risk factors for metabolic syndrome: high blood pressure and low HDL (good) cholesterol (for nut consumers)
- Less likelihood of having four risk factors for metabolic syndrome: abdominal obesity, high blood pressure, high fasting glucose and a lower prevalence of metabolic syndrome (for tree nut consumers)
"Nut/tree nut consumption was associated with a decreased prevalence of selected risk factors for cardiovascular disease, type 2 diabetes, and MetS [metabolic syndrome]."
Other research has further proven that nuts, such as almonds, confer superior heart health benefits to complex carbs like whole-wheat muffins; a study in the journal Circulation found people with abnormally high level of lipids, such as cholesterol, in their blood, were able to significantly reduce their risk factors for coronary heart disease by snacking on whole almonds.i Those who snacked on whole-wheat muffins got no such benefit.
It's likely that nuts impact your heart health in numerous ways. For instance, many (walnuts, hazelnuts, pecans, Brazil nuts, almonds, cashews and peanuts) contain the amino acid l-arginine, which offers multiple vascular benefits to people with heart disease, or those who have increased risk for heart disease due to multiple cardiac risk factors. L-arginine is a key nutrient in promoting efficient blood flow and overall cardiovascular function. L-arginine is considered one of the "semi-essential" amino acids—meaning, often your body can't produce it in sufficient quantities, so you must obtain adequate quantities from your diet.
Will Eating Nuts Make You Fat?
It's one of the biggest nutritional myths of all times that eating a food high in healthy fat will make you fat. If you're watching your weight, a small handful of nuts like almonds is a better snack choice than a snack high in complex carbohydrates, such as a bran muffin. In one study comparing those who ate a low-calorie diet that included either almonds or complex carbs, the almond group had a:ii
- 62 percent greater reduction in their weight/BMI
- 50 percent greater reduction in waist circumference
- 56 percent greater reduction in body fat
A separate study in the journal Obesity also found that eating nuts two or more times per week was associated with a reduced risk of weight gain.iii
Which Nuts are Healthiest?
You can't really go wrong when choosing nuts to eat, as long as you pay attention to quality. By this I mean look for nuts that are organic and raw, not irradiated or pasteurized (see below for more details). One exception is peanuts, which I typically avoid, and which are technically in the legume family. Along with being one of the most pesticide-laden foods you can eat, most peanuts are also contaminated with aflatoxin, a carcinogenic mold. My favorite nuts are pecans, walnuts, almonds and hazelnuts. Generally speaking, each type of nut will offer a slightly different mix of nutrients for your health. For instance:
- Almonds: One of the healthiest aspects of almonds appears to be their skins, as they are rich in antioxidants including phenols, flavonoids and phenolic acids, which are typically associated with vegetables and fruits. As the Almond Board of California reported, a study in the Journal of Agricultural and Food Chemistry even revealed that a one-ounce serving of almonds has a similar amount of total polyphenols as a cup of steamed broccoli or green tea.iv
- Walnuts: Walnuts are good sources of plant-based omega-3 fats, natural phytosterols and antioxidants that are so powerful at free-radical scavenging that researchers called them "remarkable."v Plus, walnuts may help reduce not only the risk of prostate cancer, but breast cancer as well.
- Pecans: Pecans contain more than 19 vitamins and minerals, and research has shown they may help lower LDL cholesterol and promote healthy arteries.
- Brazil Nuts: Brazil nuts are an excellent source of organic selenium, a powerful antioxidant-boosting mineral that may help prevent cancer.
Most Almonds in North America are Pasteurized -- Even if They're Labeled Raw
Unfortunately, it is difficult to find raw almonds in the United States, because the U.S. Department of Agriculture implemented a mandatory pasteurization program for almonds in 2007. The Almond Board of California states they have conducted independent nutritional lab analyses that show pasteurization does not degrade the nutritional value of almonds, but this is also what is falsely claimed for pasteurized milk -- that the pasteurization process does not change its nutritional composition, or allergenicity. We know, however, that raw milk and pasteurized milk are two very different foods from a health standpoint, and it stands to reason that raw and pasteurized almonds are too.
The Almond Board of California again states that the pasteurization processes for almonds are slightly different from the one used for milk and juice in that they only treat the surface of the nut, but the Cornucopia Institute states the USDA mandate "requires sanitation of almonds with a toxic fumigant or treatment with high-temperature heat."viSo please be aware that if you purchase almonds in North America, they will have gone through one of the following pasteurization methods:
- Oil roasting, dry roasting, or blanching
- Steam processing
- Propylene Oxide (PPO) treatment (PPO is a highly toxic flammable chemical compound, once used as a racing fuel before it was prohibited for safety reasons)
Pasteurized almonds sold in North America can still be labeled "raw" even though they've been subjected to one of the treatment processes listed above. There are generally no truly "raw" almonds sold in North America, so don't be misled. It is possible to purchase raw almonds in the U.S., but it has to be done very carefully from vendors selling small quantities that have a waiver from the pasteurization requirement. The key is to find a company with the waiver that is NOT pasteurizing them. I personally enjoy raw almonds nearly every day, as it is an outstanding food.
Eating Nuts in Moderation is Best
You need to be cautious with the quantity of nuts you eat, but this is not because they will make you "fat," as many believe. Instead, the reason for moderation is that almost all nuts are top heavy in omega-6 fats and can upset your omega-6/omega-3 ratio. As explained by Dr. Paul Jaminet, a trained astrophysicist and author of the book, Perfect Health Diet:
"It's really important to be low in omega-6 fats … When you're eating low-carb, you're necessarily eating a high-fat diet, and the quality of your fats becomes very important. It's very important to keep down the level of omega-6 fats, because the polyunsaturated fats in general become toxic if you get too much. That's where you really have to avoid all these vegetable oils, because they can be very high in omega-6. Things like corn oil, safflower oil, soy bean oil – even canola oil – just have too much polyunsaturated fat."
Nuts also contain polyunsaturated fats, and certain nuts, like pistachios and cashews, contain slightly higher amounts of carbohydrates than nuts like almonds and walnuts, which is important to keep in mind if you're following a low-carb diet, and especially if you have high levels of insulin, high blood pressure, excess weight, high cholesterol or diabetes.
- i Circulation. 2002 Sep 10;106(11):1327-32.
- ii Int J Obes Relat Metab Disord. 2003 Nov;27(11):1365-72.
- iii Obesity (2007) 15, 107–116; doi:10.1038/oby.2007.507
- iv J. Agric. Food Chem., 2006, 54 (14), pp 5027–5033
- v Antioxidative Polyphenols from Walnuts, Phytochemisty, August 2003: 63(7); 795-801, Toshiyuki Fukuda, et al.
- vi The Cornucopia Institute, The Authentic Almond Project