November 2017 update from Daisy Buckingham ANutr Registered Associate Nutritionist
Further Studies Showing Nuts Are Good For Health
A recent study looked at over 92,946 women at the Nurses’ Health Study II (1991 to 2013), and 41,526 men from the Health Professionals Follow-Up Study (1986-2012), all of whom were free of cancer, heart disease, and stroke at the baseline.
They found with follow-ups that there were 14,136 incidents of cardiovascular disease cases, including 8,390 coronary heart disease cases, and 5,910 stroke cases. They found that total nut consumption was inversely associated with total cardiovascular disease, and coronary heart disease.
Participants that consumed 5 or more servings of nuts per week, had a 14% lower risk of cardiovascular disease, and 20% lower risk of coronary heart disease. Those who consumed walnuts, one or more times per week had an association of 13%-19% lower risk of total cardiovascular disease and 15-23% lower risk of coronary heart disease (Guasch-Ferré et al., 2017).
Reference:
Guasch-Ferré, M. Liu, X. Malik, VS. Sun, Q. Willet, WC. Manson, JE. Rexrode, KM. Li, Y. Hu, FB. And Bhupathiraju, SN. (2017). Nut consumption and risk of cardiovascular disease. Journal of the American College of Cardiology available here.
Daisy is a Registered Associate Nutritionist with a Master's Degree in Public Health Nutrition, which is Association for Nutrition (AFN) accredited. She, also, has a BSc degree in Psychology and Cognitive Neuroscience; and has completed an AFN accredited Diet Specialist Nutrition course and is currently studying for a PgDip in Eating Disorders and Clinical Nutrition.
Daisy has worked for an NHS funded project, the Diabetes Prevention Programme; and shadowed a nutritionist in Harley Street.
Any information provided by us is not intended to diagnose, treat, cure or prevent disease. We always recommend referring your health queries to a qualified medical practitioner.
The following is a guest blog by Vicky Ware,
Nuts for Health
Nuts are really great for health — a number of studies have found eating a handful of nuts a day is associated with reduced ‘all-cause morbidity’. This means nut-eaters are less likely to die from any cause. Nuts and nut butter a great way to consume a nutrient dense filling snack when you’re feeling peckish.
Although nuts are calorie dense, regularly eating them seems to prevent weight gain1. They’re also good for the heart — in one study people who ate nuts at least 4 times per week were 37% less likely to suffer from heart disease than people who hardly ever ate nuts — and every time people added a portion of nuts to their diet they reduced their chances of heart disease by 8%2! (Note: These studies do not say 'how many' nuts merely that they were eating nuts. The reason for this is because they want to capture 'real life' experiences of people's diets over a long term period of time. Therefore, they look at health outcomes for people who already 'eat nuts' rather than telling people to 'eat 8 nuts/day for 5 years', for example.)
Why Are Nuts So Great for Health?
Regularly eating nuts improves markers of inflammation in the body along with reducing people’s risk of suffering from cardiovascular disease or type 2 diabetes3. In fact, swapping 3 servings of red meat, eggs or refined grains per week for 3 servings of nuts significantly reduces a key marker of inflammation in the body3. Inflammation has been linked to cardiovascular disease, cancer, neurological conditions, autoimmune disorders and even depression and anxiety, so the anti-inflammatory nature of nuts could be the reason for their health-giving effect 4;5.
Inflammation is a delicate balancing act. Although too much is a bad thing, inflammation is the process of your immune system activating to heal an injury or fight an infection. Without inflammation, a graze on your skin wouldn’t heal and any bacteria that entered your body through the graze wouldn’t be killed by the immune system. So, we don’t want to get rid of inflammation completely but you also don’t want inflammation to be over-zealous or continue for too long after an injury or illness has healed.
Your body is capable of maintaining this balance but only if your diet contains adequate nutrients. What you eat contains the building blocks your body will use to build the components of the immune system. Certain foods result in a more inflammatory immune system — for example those containing omega-6 fatty acids - while others result in a ‘calmer’ less inflammatory immune system — omega-3 fatty acids (contained in walnuts) fall into this camp.
The type of bacteria in your gut, also have an impact on the immune system and inflammation. The foods you eat affect which bacteria can survive in the gut, after all they can only eat what you eat. Nuts contain fibre which is a food for bacteria living in the gut, but they also contain antioxidant compounds like polyphenols which are anti-inflammatory. It’s this anti-inflammatory effect which might be responsible for the beneficial health effect caused by eating nuts.
Specific Nuts & Their Health Benefits
Many of the studies suggesting a handful of nuts are good for health used different kinds of nuts from peanuts to walnuts to a mixture so really it’s up to you which you choose to eat. There are studies on specific nuts though and some of these are summarised below…
- Cashews are relatively low in fat compared to other nuts — although the fat content of other nuts doesn’t appear to be a problem for health and, in fact, the fats in nuts appear to be one of the reasons they’re so good for you. Over 50% of the fats in cashews are monounsaturated fats which are thought to be good for cardiovascular health6.
Micronutrients: 28grams(approximately one serving) of cashew nuts contain 5% of your recommended daily potassium, 10% of your protein, 10% of your iron, 5% of your B6 and 20% of your magnesium.
- Brazil nut intake, even after just one serving, was shown to improve the blood lipid profile of people taking part in a study shortly after eating the nuts7. They have also been found to improve the blood lipid profile of obese people — potentially because they contain unsaturated fats and bioactive compounds such as polyphenols which act as antioxidants in the body8.
Asparagus Risotto with Ricotta and Crushed Brazil Nuts
Eating whole foods that contain antioxidants is associated with reduced incidence of some cancers and lower general inflammation in the body9. Brazil nuts are one of the best sources of the essential micronutrient selenium and potentially because of this, they improve cognitive function in older people — poor cognitive function may be due to too few antioxidants, such as selenium, in the body10.
Micronutrients: 28 grams of brazil nuts contain 8% of your daily fibre, 4% calcium and 26% of your magnesium. However, this amount would contain a whopping 767% of your daily selenium meaning regular intake of this number of brazil nuts could lead to selenium poisoning. 400mcg is the tolerable upper limit for selenium intake for adults, more than this per day can result in selenium poisoning. 6 nuts contain around 544mcg of selenium11. So, although it’s unlikely you’ll suffer from selenium poisoning — you’d have to eat 6-ish nuts a day for a while — it’s best to eat brazil nuts relatively sparingly12.
- Peanuts like many other nuts, contain bioactive nutrients — compounds found in foods which are known to have a direct effect on the body.
Peanuts are known to contain bioactive nutrients thought to be good for blood vessel health. The elasticity of blood vessels, essential to maintain good blood pressure, improves when people have peanuts in their diet (in this case around 60g per day) and amazingly short-term memory and other measures of brain health were also better when people had peanuts in their diet13. These benefits also come from peanut butter, just be sure to eat the versions which are 100% peanut rather than those with added sugar, salt and palm oil which have fewer nuts and therefore fewer of the health benefits of nut consumption.
Micronutrients: 28 grams of peanuts contain 9% of your daily recommended dietary fibre, 11% magnesium, 2% calcium, 5% vitamin B6 and 7% iron.
- Walnuts are good for gut health — reducing incidence of colon cancer in mice — potentially due to the changes they induce in the bacteria present in the gut14.
Carrot Cake with Walnuts
Walnuts contain high levels of phytochemicals, including polyunsaturated fatty acids which may be one reason they seem to be good for brain health15. Walnuts contain plenty of fat, manganese, iron, copper, protein, phosphorus, calcium and magnesium16.
Looking at whole-diets, adding walnuts, almonds and hazelnuts to a Mediterranean diet lead to reduced waist circumference and BMI compared to people eating a low-fat diet17.
Walnuts also contain omega-3 fats which tend to be lacking in Western diets and are essential to keeping the immune system healthy. Humans evolved eating equal amounts of omega-3 and omega-6, or possibly more omega-3 than omega-6. Now, we tend to eat around 15 times the amount of omega-6 which leads to inflammation in the body18;19. Walnuts are a great way to top up the amount of omega-3 in your diet.
Micronutrients: 28 grams of walnuts contain 2% of your daily recommended calcium, 4% iron, 10% vitamin B6 and 11% of your magnesium.
- Almonds eaten as a snack (43 grams of them, which would contain around 250 calories) reduce blood glucose levels along with improving other markers of metabolic health, while also reducing hunger including during a meal eaten later that day20.
Almonds are rich in nutrients, including phytonutrients, magnesium, copper, fat and fibre — the latter two are thought to be the reason almonds have a beneficial effect on blood cholesterol21.
They also improve metabolic and inflammatory markers21. Eating almonds has also been shown to improve the overall quality of someone’s diet — they ate fewer ‘empty’ calories and increased their intake of other nutrient dense foods like vegetables — along with changing the kind of bacteria in the gut22.
Micronutrients: 28 grams of almonds contain 14% of your daily recommended fibre, 12% of your protein, 7% of your calcium, 6% of your iron and 19% of your magnesium.
- Hazlenuts are linked with reduced blood pressure and inflammation in the body. It’s not known exactly why including hazlenuts in the diet has these effects, but again it’s probably due to their nutrient density, fat content and fibre. One study found that people who ate 30g of hazelnuts, walnuts and almonds per day, for 12 weeks saw improvements in metabolic markers which could mean reduced chance of metabolic syndrome23.
Micronutrients: 28 grams of hazlenuts contain around 10% of your recommended fibre, 7% of your iron, 10% of your B6 and 11% of your magnesium.
14 walnut halves (around 28 grams or 7 whole walnuts) is a guide to the amount of nuts you should eat in a day to gain health benefits — either of one type of nut (and change the type you eat daily) or a mixture of nuts each day.
Although nuts are high in calories, they’re appetite satiating and studies show people who snack on them tend to lose weight, or at least not gain weight24;25. This could be for multiple reasons. The high fibre and fat content of nuts makes them very satiating — you won’t feel hungry after eating them, meaning you don’t snack on other foods.
The fats in nuts may also alter metabolism, meaning you burn more body fat stores as fuel. Some research has even shown that people who eat nuts absorb less fat from the food they eat, reducing calorific intake of all foods they eat26.
Roasted/Salted Nuts: Still Healthy?
Some research suggests that lightly salting and roasting nuts doesn’t affect how healthy they are, with both roasted and un-roasted hazelnuts resulting in the same improvements in markers of health in one study27.
However, the temperature the nuts are roasted at will affect their nutrient content. High temperatures (above 160°C) reduce the polyphenol content of nuts — these temperatures will be reached if nuts are deep fried or roasted at too high a temperature28.
Roasted or fried nuts also tend to come heaped with salt high in sodium. Too much sodium in the diet can increase blood pressure and is linked to cardiovascular disease29. Western diets tend to contain too much sodium already, so if you’re going to eat nuts daily for the health benefits it’s best to eat ones not covered in salt.
For extra flavour, you could try experimenting with chilli flakes or grinding nuts and putting them in porridge or smoothies.
So, if you gently roast nuts it could improve their flavour — depending on personal preference — without detrimentally affecting their nutrient content. But if you’re going to buy pre-packaged nuts it’s best to go with raw, whole nuts to reap the biggest health benefits without added salt, oil used for frying or reduction in nutrient content.
Nut 'Milks' and Milk Alternatives
There seems to be an ever expanding alternative to the dairy milk section in every supermarket I’ve been in recently and as someone who has a dairy-free diet this is something I’m pretty happy about.
Personally, I intentionally mix things up with my nut-milk intake (sometimes even going for non-nut varieties like coconut (which is technically a seed) and oat milk). In my experience different kinds of nut milk are best for different uses.
Coconut: nice and creamy and lovely as a drink, on cereal or in porridge. It also contains medium-chain triglycerides (MCTs) which have myriad health benefits30.
MCTs are quickly absorbed and used as energy by the body, unlike other fats which have to be broken down first. This may be the reason they’ve been found to improve the endurance exercise performance of mice31.
They also seem to increase metabolic rate, which may be why people who consume them have lower body fat especially stomach fat which is associated with poor metabolic health32. Along with increasing metabolic rate and therefore calories burned, MCTs also satiate appetite meaning people who eat them eat less other food during a day33;34.
In fact, people who eat MCTs for breakfast, eat fewer calories at lunch time, meaning using coconut milk in your breakfast cereal could curb snacking and calorie intake at lunchtime while ensuring you’ve got enough energy to power through the morning. This milk is normally sold with added calcium to make this a replacement for the calcium you’d usually get in ‘actual’ dairy milk.
Almond: another nice thick milk which I find works well as a milk replacement in baking for e.g. pancakes or Yorkshire puddings which some of the less fatty milks (e.g. oat) don’t seem to do quite so well.
Neutral flavour (doesn’t have that typical almond-y marzipan flavour) so great for anything you don’t want to taste strongly nutty. Not quite so nice if you want a glass full as a drink — although this is obviously personal preference.
A delicious hot chocolate made with nut milk
Hazlenut: Though some nut milks don’t have a strong nutty taste, this one does taste of hazlenuts. It is great for using in baking something like a hazelnut chocolate cake.
Nut milks are not an exact replacement for dairy which contains different protein, fats and more calories.
Conclusion
In summary, it appears nuts are pretty good for health. They’re packed with essential micronutrients, protein, fat and fibre and this combination appears to be behind the fact that people who eat them regularly are healthier than people who don’t.
There are lots of ways to incorporate nuts into your diet and they each have a different flavour, meaning if you don’t like one you can shop around until you find one you do like.
Nut butters and milks are another great way to add some nutty nutrition to your daily diet.
Vicky,
Vicky has a degree in Biological Sciences with a focus on biochemistry and immunology and is currently studying for a MSc in Drug Discovery and Protein Biotechnology. She is also an endurance athlete.
About Lucy Bee
Any information provided by us is not intended to diagnose, treat, cure or prevent disease. We always recommend referring your health queries to a qualified medical practitioner.
Lucy Bee is a lifestyle brand selling food, skincare and soap products all completely free from palm oil and with minimal use of plastic. Lucy Bee is concerned with Fair Trade, organic, ethical and sustainable living, recycling and empowering people to make informed choices and select quality, natural products for their food and their skin.
The views and opinions expressed in videos and articles on the Lucy Bee website/s or social networking sites are those of the author/s and do not necessarily reflect those of Lucy Bee Limited.
References
1. Bes-Rastrollo (2007) Nut consumption and weight gain in a Mediterranean cohort: The SUN study.
2. Nutrition Data (2016) Cashew Nuts
3. Yu (2016) Associations between nut consumption and inflammatory biomarkers.
4. Blomhoff (2006) Health benefits of nuts: potential role of antioxidants.
5. Almond (2013) Depression and inflammation: Examining the link.
6. Ruiz-Canela (2016) The Role of Dietary Inflammatory Index in Cardiovascular Disease, Metabolic Syndrome and Mortality.
7. Colpo (2013) A single consumption of high amounts of the Brazil nuts improves lipid profile of healthy volunteers.
8. Maranhao (2011) Brazil nuts intake improves lipid profile, oxidative stress and microvascular function in obese adolescents: a randomized controlled trial.
9. Colpo (2014) Brazilian nut consumption by healthy volunteers improves inflammatory parameters.
10. Cardoso (2016) Effects of Brazil nut consumption on selenium status and cognitive performance in older adults with mild cognitive impairment: a randomised controlled pilot trial.
11. National Institutes of Health (2016) Selenium Dietary Supplement Fact Sheet.
12. Lemire (2012) No evidence of selenosis from a selenium-rich diet in the Brazilian Amazon.
13. Barbour (2016) Cerebrovascular and cognitive benefits of high-oleic peanut consumption in healthy overweight middle-aged adults.
14. Nakanishi (2016) Effects of Walnut Consumption on Colon Carcinogenesis and Microbial Community Structure.
15. Poulose (2014) Role of walnuts in maintaining brain health with age.
16. Moyib (2015) Potentials of raw and cooked walnuts (Tetracapidium conophorum) as sources of valuable nutrients for good health.
17. Alvarez-Perez (2016) Influence of Mediterranean Dietary Pattern on Body Fat Distribution: Results of the PREDIMED-Canarias Intervention Randomised Trial.
18. Simopoulos (2002) The importance of omega-6/omega-3 essential fatty acids.
19. Simopoulos (2008) The importance of omega-6/omega-3 fatty acid ration in cardiovascular disease and other chronic diseases.
20. Tan (2013) Appetitive, dietary and health effects of almonds consumed with meals as as snacks: a randomised controlled trial.
22. Burns (2016) Diet quality improves for parents and children when almond are incorporated into their daily diet: a randomised, crossover study.
23. Tulipani (2011) Metabolomics unveils urinary changes in subjects with metabolic syndrome following 12-week nut consumption.
24. Yen Tan (2014) A review of the effects of nuts on appetite, food intake, metabolism, and body weight.
25. Ros (2010) Health benefits of nut consumption.
26. Sabate (2003) Nut consumption and body weight.
27. Tey (2016) Do dry roasting, lightly salting nuts affect their cardioprotective properties or acceptability?
28. Scholrmann (2015) Influence of roasting conditions on health-related compounds in different nuts.
29. Appel (2006) Dietary approaches to prevent and treat hypertension.
30. St-Onge (2002) Physiological Effects of Medium-Chain Triglycerides: Potential Agens in the Prevention of Obesity.
31. Fushiki (1995) Swimming endurance capacity of mice is increased by chronic consumption of medium-chain triglycerides.
33. Stubbs (1996) Covert manipulation of the ration of medium- to long-chain triglycerides in isoenergetically dense diets: effect on food intake in ad libitum feeding men.
34. McClernon (2007) The effects of a low-carbohydrate ketogenic diet and a low-fat diet on mood, hunger, and other self-reported symptoms.