Peanuts pop up everywhere – as party snacks, in the fave peanut butter and jelly sandwich and as a major ingredient in trail mix, marketed as a health food.

The popularity of this humble bean (peanuts are a legume that grows underground, unlike most nuts that grow on trees) took off in North America in the lean second world war years, when goober peas, as they are sometimes called, were promoted as a cheap source of protein.

Really, though, how healthy are they? We all know that even trace amounts can be life-threatening to someone with a peanut allergy, but what about the rest of us?
On the plus side, peanuts are a good source of potassium, magnesium, zinc and selenium, all important minerals. They also supply B vitamins, vitamin E, fibre and essential fatty acids. Studies have shown that peanuts contain resveratrol, the antioxidant that produces red wine's heart-protective effects. Peanut consumption also lowers triglyceride levels; elevated triglycerides are a risk factor for heart disease.

But their critics say that the majority of nuts on the market today are contaminated with wellness-zapping moulds and possibly even trace amounts of aflatoxins, poisons produced by a particular type of fungus. Health Canada inspects for the highly carcinogenic aflatoxins, but given the living nature of moulds, it's impossible to reduce your risk of exposure to zero. Mould toxins can affect both organically and conventionally grown crops.
Issues of contamination aside, some consider this legume difficult to digest and not suitable for daily consumption even by the healthy. Others note the peanut's hormonal properties: it has been used to encourage breast milk production and ease menopausal symptoms.
The upshot is, we decided it was time to spread a little skepticism about this everyday munchy.

What the experts say

"There isn't a single peanut in North America that isn't contaminated with mould. Aside from people who have deathly allergies, many who are feeling chronically ill for other reasons may be very sensitive to mould. Healthy people should also stay away. If you have too much of these moulds in your system, it can affect your immunity. I don't know what the safe level is. There's something wrong with every food, but this is really an avoidable disease-causer. I think peanuts probably should be banned."
ZOLTAN RONA , MD, MSc, Toronto

"Peanut butter is one of the foods in which pesticide residues have been found most frequently. Another issue is that peanuts contain omega-6 fatty acids. If peanuts become part of your regular diet and you're also consuming other foods high in omega-6 fats, it could throw off your balance between omega-3 and omega-6 oils. Nuts that contain omega-3 oils would be better. I recommend raw almond butter and raw almonds and walnuts. If people are looking for peanut butter, an organic brand from New Mexico is better because it's so dry there that peanuts don't have a lot of aflatoxins. I pour the oil off the top, which gets rid of the omega-6s, and if the peanut butter is dry add a little olive oil."
JANESS TOMLINSON , holistic nutritionist, Toronto

"Heat and fats don't go together in terms of health benefits, but roasted peanuts are still beneficial. The fibre and protein will be unharmed by the roasting process. The quality of the fats won't be as good, but peanuts still have a good fatty acid profile. A good serving size is about 15 to 20 peanuts. We don't need to worry about aflatoxins. They develop in warm, humid storage conditions. We have good-quality conditions here. The government checks for aflatoxins and has storage standards, so you should only find aflatoxins in trace amounts, if at all. Still, you shouldn't have peanuts or peanut butter every day. There are many natural toxins in foods; that's one reason to vary your food supply. Never eat mouldy or stale and dry nuts.''
SUSAN FYSHE , registered dietitian with Healthy Lifestyle Nutrition, Toronto

"Peanuts are good for people whose metabolism, from a traditional Chinese medicine (TCM) perspective, is too high, who are always hungry, always eating. But many of us are not like that - in fact, our digestion is sluggish, especially vegetarians, and peanuts slow the digestion down even more, causing dampness in TCM terms. The signs of dampness include sluggish energy, bloating, indigestion, loose stools and weight gain. Organic peanuts are better, and it's best to avoid the hydrogenated fat and icing sugar in the regular peanut butter and get the stuff that's just made out of peanuts."

Dr. KALEB MONTGOMERY , Doctor of traditional Chinese medicine, Toronto

"The combination of bread and peanut butter creates a lot of dampness in the body. It's also easy to take peanut butter in excess because it's more concentrated. If there are high levels of toxicity in the body, peanuts are also not advised because they are hard on digestion. Even for those who don't have any known allergies or indigestion, (it's best to avoid eating) peanuts with milk, dairy products or fruit juices. Peanuts are best eaten by themselves. They do have therapeutic uses and might be prescribed as part of an Ayurvedic regime. It really depends on the individual."
ISMAT NATHANI , Ayurvedic neurotherapist, Toronto

NOW | OCT 21 - 27, 2004 | VOL. 24 NO. 8