How Healthy are Nuts?

One of the principle foods we’re told to include in our diet is nuts. Nuts are  a very popular bar snack, particularly coated in salt or seasonings. Many avoid them due to their very high calorie content – so how healthy are nuts, and are they as fattening as we think?

Nuts are one of the most popular snack items in the modern world, with global production increasing year on year since 2007 – almonds are by far the most popular nut. Asia consumes the most by proportion (but they have the highest population) and the US by country (source: International Nut & Dried Fruit)

What are Nuts?

We’ve come to use the word nut to describe a whole range of foods that are not really nuts at all! Nuts are fruits that have dried out with only one (sometimes) two seeds! The seed becomes encased within a very hard shell as it matures.

Not all nuts are edible, so we’ve come to use the terms culinary nuts (those we can eat) and botanical.

True nuts only include: hazelnuts and chestnuts – so why nuts have become used for a small minority of these foods is baffling.

All other nuts are not nuts at all! Most of them are drupes: cashews, almonds, pistachio, walnuts, pecans, macadamia and coconuts.

Peanuts are legumes (closer to peas than nuts)

Brazil nuts and pine nuts are seeds, but cashews and pistachios are also considered seeds and are interchangeably known as both drupes and seeds.

Nut Allergies

Understanding nut allergies is truly important for anyone working in catering or the food industry.

With nut so poorly defined, what do we really mean by nut allergy? Basically, there are two types of nut allergy:

• peanut allergy – probably the most well known now. This is a serious allergy to the protein in peanuts and may often infer that at least one tree nut also causes allergy
• tree nut allergy – which specifically refers to walnut, brazil nuts, almonds and hazelnuts, despite only one of those being a true nut. However, allergy sufferers have to avoid all tree nuts including macadamia, pine nuts, pecans, and any nut grown in a hard shell.

Cross contamination is common with nut products, and the usage of them from food to personal products is ubiquitous – it’s in everything. Avoiding tree nut proteins is a nightmare for tree nut allergy sufferers.

But so what if they do, they’ll just get a rash right?

Absolutely not! This is a serious problem – it can (and does!) kill people. Seeing someone experiencing an allergic attack is a very traumatic and harrowing experience for all concerned.

Nut Nutrition

Nuts are rich in unsaturated fats, fibre, minerals, vitamins and phytonutrients [1,2,3], but they are also very high in calories (see table below).

Because of this, nutritionists and dietitians often recommend nuts in very small proportions (usually 25-30g per day) in order to avoid weight gain.

However, the evidence that nut consumption actually contributes to weight is missing – despite the fact that they’re high in fat and thus high in energy.

Recent evidence is now suggesting that this could be because nuts do not give up their energy easily but also because nuts are satisfying and so we tend to consume less calories overall [4,5,6].

A number of studies have been conducted that show that snacking on nuts may not contribute to weight gain because:

• Nuts have a compensatory effect on our overall diet, so we tend to consume less calories elsewhere in our diet because nuts are satiating [7, 8, 9]
• The fats in nuts do not absorb well, our bodies aren’t great at getting the fat out of the nut [10, 11, 12]
• The energy our bodies use to specifically digest nuts could be higher [13, 14]
• Nuts have a prebiotic effect and thus feed the bacteria in the gut – this relationship humans have with bacteria in the gut could impact on the propensity to obesity [15, 16]
• One of the reasons that we may not be getting the energy out of (whole) nuts is because we don’t chew long enough. Digestion starts in the mouth [17, 18]. This wouldn’t account for smooth nut butters of course.

Nut	Calories	Total Fat	Protein	Total Omega-3	Top Mineral/Vitamin
Chestnut	196kcal	1.3%	1.6%	53mg	Vitamin C 67% DV
Cashew	553kcal	43.8%	18.2%	62mg	Vitamin K 43% DV
Pistachio	557kcal	44.4%	20.6%	254mg	Vitamin B6 85% DV
Peanut	567kcal	49.2%	25.8%	3mg	Folate, Vitamin B3 60% DV
Almond	575kcal	49.4%	21.2%	6mg	Vitamin E 131% DV
Hazelnut	628kcal	60.7%	15%	87mg	Vitamin  B1 43% DV
Walnut	654kcal	65.2%	9.2%	9079mg	Vitamin B6 27% DV
Brazil	656kcal	66.4%	14.3%	18mg	Selenium 2739% / vitamin B1 41% DV
Pine Nut	673kcal	68.4%	13.7%	112mg	Vitamin K 67% DV
Pecan	691kcal	72%	15.2%	986mg	Vitamin B1 44%
Macadamia	718kcal	75.8%	7.9%	206mg	Vitamin B1 80% DV
Based on 100g raw nuts Source: NutritionData.com

Minerals and Vitamins

Most nuts are high in either manganese or copper, with the exception of brazil nuts which are a very high source of selenium.

All nuts are incredible source of vitamin B complex, with others offering vitamins C, E and K, as well as phytonutrients, compounds found only in plants that are considered by some to have antioxidant powers which contribute to protection against many diseases including cancer.

Phytonutrients are also loved by our gut bacteria, and therefore daily consumption of nuts will keep the good bacteria in our gut happy and happy bacteria ensures long term good health for their host – at least, according to emerging studies.

Almonds are by far the most popular snack – but including a few brazil nuts adds selenium to our diet, which is particularly important for vegans. Pine nuts, whilst higher in fat, are a great source of vitamin K!

And if you have a desk job, then having a small pot on your desk to snack on throughout the day is a perfect addition to your diet and could even have you eat less the rest of the day.

Most supermarkets sell bags of mixed raw nuts – make sure you have some in your shopping basket.

Image Credit
Monfocus at Pixabay.com