About Nuts update

In the July 2007 newsletter you could read that the About Nuts website is available in different European languages. About Nuts is even expanding further into Europe. Starting now, About Nuts will also send the newsletter to stakeholders in Germany, Switzerland and Austria. In these countries you can also find the About Nuts-logo on the package of the ‘Jack Klijn’ brands in these countries.

A word from: Alix Bruens, Dutch Heart Association

Are peanuts and nuts essential in a healthy diet?

The consumption of (pea)nuts protects according to several epidemiological studies against the development of cardiovascular diseases. It is still not clear whether these health benefits result from their beneficial fatty acid composition or their relative high content of antioxidants, fibres, vitamins, minerals and phytosterols. Or could their protective effect also be a result of the combination of these nutrients.

You might think that the message ‘a portion of nuts a day keeps the doctor away’ is an easy one to communicate. The question is, are there also disadvantages to (pea)nuts? A possible negative aspect of (pea)nuts is their high energy content. (Pea)nuts have a high caloric content. The intake of calories has become very important in these times that prevention of overweight is emphasised.

An other question is, when are (pea)nuts consumed? Usually as a snack at parties. Often when having a drink for dinner or in the evening. The disadvantage of serving (pea)nuts at parties is that most people are hungry at that time of the day and will eat quite a bit. If you eat them instead of cheese, sausages or salty crackers, then they are quite a good choice. Cheese and sausages have a relatively high calorie content and additionally contain a lot of saturated fat and salt. While (pea)nuts have the advantage that they are naturally salt free.

Decreasing salt intake is very important in preventing high blood pressure. For weight management on the other hand it is important to eat a moderate amounts of (pea)nuts. According to the criteria for the Ik Kies Bewust-logo (a common Dutch healthy choice logo) a snack should provide a maximum of 110 calories. Table below shows that this equals almost 1 spoon (=20 grams) of (pea)nuts.

Source: Dutch Nevo-table 2006

From the above table one can conclude that when you eat a moderate amounts of (pea)nuts you will benefit from the advantages of (pea)nuts, but will not jeopardise their bodyweight. Additionally it is also possible to consume processed (pea)nuts. You can think of using peanut butter or other nut spreads on a sandwich. If these spreads are served as a replacement for cheese or high fat meat products, this should be preferred based on their favourable fatty acid. So we can concluded that within a varied diet (pea)nuts can be included.

References:
1) Gezondheidsraad. Richtlijnen Goede voeding. Den Haag Gezondheidsraad 2006; publicatie 2006/21
2) Nevo-tabel 2006
3) Voeding Nu, april 2007, nr.4

Science and health – HEART HEALTH SPECIAL

Heart health benefits of peanuts and tree nuts

Epidemiological studies consistently point out a strong protective effect of nut consumption on cardiovascular diseases. This can most likely be attributed to (a combination of) the beneficial components present in (pea)nuts. In this newsletter, About Nuts presents an update on the scientific evidence.

Epidemiological evidence

Many epidemiological studies have investigated the effect of (pea)nut consumption on the occurrence of coronary heart disease (CHD). The largest prospective studies are the Adventist Health Study ¹, the IOWA Women’s Health Study ², the Nurses’ Health Study ³ and the Physicians’ Health Study ⁴. These four studies, as well as a number of smaller studies, show a consistent and strong cardio-protective effect with increased (pea)nut consumption. Kelly et al ⁵ reviewed the evidence and concluded that the average reduction in risk of CHD death amounts to 8.3% for each serving of (pea)nuts consumed weekly (30g). The fact that intervention trials have also found reduced CHD risk factors with increased (pea)nut consumption supports, according to the researchers, this conclusion. Several components in nuts, like the fatty acids, anti-oxidants and fibres, could be responsible for these protective effects.

Fatty acids

The intake of foods rich in unsaturated fatty acids, mostly provided by the consumption of vegetable fats and oily fish, is associated with improved lipid profiles, a lower potency of intermediate biomarkers of atherosclerosis and lower incidence of cardiovascular diseases. Fat accounts for almost 50-80% of the weight in (pea)nuts, predominantly present in the form of unsaturated fatty acids. An impressive amount of evidence from clinical studies demonstrates that tree nut consumption improves the lipid CHD risk factor profile. Incorporation of tree nuts in the diet has also been found to reduce LDL-cholesterol by 3-19% compared to western and lower fat diets ⁶.

Antioxidants

As other vegetable products, nuts and peanuts contain numerous types of antioxidants with different properties. Several nuts are among the dietary foods with the highest content of total antioxidants. Of the tree nuts, walnuts, pecans and chestnuts contain the most antioxidants. Peanuts contain less, but still considerable amounts. Antioxidants play a role in the inhabitation of oxidative stress. Since oxidative stress is common in chronic degenerative disease (as heart disease), it has been assumed that dietary antioxidants exert a protective effect. The high level and complex mix of antioxidants in (pea)nuts can probably explain -at least partly- their cardio-protective effects. However, it is yet too early to conclude whether this effect is specific to the antioxidants ⁷.

Fibre

Also fibres can contribute to the protective effect. Pea(nuts) are, after whole grain cereals, the second highest natural source of dietary fibre. There is considerable epidemiological evidence to support an inverse relationship between the intake of fibre and cardiovascular risk, as was reviewed by Salas-Salvadó et al ⁸.

Vitamins, minerals and phytosterols

Pea(nuts) contain significant amounts of essential micronutrients, to which cardio-protective effects are attributed, like folate and the minerals potassium, calcium and magnesium. Furthermore, they are rich in phytosterols that can help lower blood cholesterol ⁹.

Source: Nutrition tables by USDA 2002 and Dutch Nevo-table 2006

Conclusion

There is a substantial amount of evidence to support a cardio-protective role of peanuts and tree nuts. This protective role probably takes effect through different mechanisms, with different nutrients and bioactive substances involved. To what extend all these different beneficial components contribute to the cardio-protective effect is yet unknown.

References
1) Fraser GE et al. (1992). A possible protective effect of nut consumption on risk of coronary heart disease. The Adventist Health Study. Arch Intern Med 152 1416-1424.
2) Kushi LH et al (1996). Dietary antioxidant vitamins and death of coronary heart disease in postmenopausal women. N Eng J Med 334 1156-1162.
3) Hu FB et al. (1998). Frequent nut consumption and risk of coronary heart disease in women: prospective cohort study. BMJ 317 1341-1345.
4) Albert CM et al. (2002). Nut consumption and decreased risk of sudden cardiac death in the Physicians’ Health Study. Arch Intern Med 162 1382-1387.
5) Kelly JH and Sabaté J (2006). Nuts and coronary heart disease: an epidemiological perspective. British Journal of Nutrition 96 S61-S67.
6) Griel AE and Kris-Etherton PM. Tree nuts and the lipid profile: a review of clinical studies. British Journal of Nutrition 96 S68-S68.
7) Blomhoff R et al. Health benefits of nuts: potential role of antioxidants. British Journal of Nutrition 96 S52-S60.
8) Salas-Salvadó J et al. Dietary fibre, nuts and cardiovascular disease. British Journal of Nutrition 96 S45-51.
9) Segura R et al. Other relevant components of nuts: phytosterols, folate and minerals. British Journal of Nutrition 96 S36-S44.