Peanut or Pea-not?

The humble peanut is much loved around the world, making up 67% of all nut consumption in the US and can be found as an ingredient in a ridiculous number of foods or eaten as a savoury snack. Unfortunately, peanut allergy is also one of the most common food allergies with about 1 in 100 people in the UK being allergic.

My interest in this topic arose when someone broke the news to me that the peanut is not actually a nut. Okay, so maybe not the most ground-shaking piece of information but a surprise to me all the same. Turns out, the peanut is actually a legume. This is because a nut is considered to be a fruit whose ovary wall become very hard at maturity, hence the phrase “tough nut to crack”. Also, nuts tend to grow on trees. In contrast, peanut pods split open when ripe and they grow underground. In fact, they are scientifically classified as Arachis hypogaea with hypogaea meaning ‘under the earth’.

Peanuts actually play a lot of roles in health and medicine. In terms of nourishment, peanuts are a great source of protein. They are richer in protein than soy beans and just two tablespoons of peanut butter has more protein than an egg. They also contain nearly 50% fat- but don’t worry! 70% of that fat is unsaturated so whilst that still makes them rather calorific, they are a very good source of energy. Mineral content such as potassium, phosphorus, iron, zinc, copper and magnesium is also proportionately high in peanuts. Finally, peanuts have a lot of vitamin B.

In relation to medicine, peanuts are rich in resveratrol which has antioxidant properties. This helps control cholesterol and prevent heart disease. Peanuts also have an abundance, it seems, of genistein which is known to combat PMS and also prevent the development of cancer cells. One of the many amino acids in peanuts is tyrosine. Tyrosine is used by our bodies to make dopamine, also known as one of the ‘happy hormones’. Lack of dopamine is actually associated with ADHD (attention deficit hyperactivity disorder) in children which can cause problems at school. However, as with everything in life I would not recommend a huge intake of peanuts just for these health benefits as anything in excess can be harmful.

Speaking of harmful, what is a peanut allergy and why does it happen? A peanut allergy occurs when the body’s immune system mistakenly believes that peanuts or something in the peanuts are harmful, so produces an immune response to attack those allergens. During an allergic reaction, histamine is released by mast cells which are found in connective tissues, like the skin. One of the effects of histamine is that it causes capillaries to become more permeable to white blood cells. As a result, fluid moves out of capillaries creating symptoms like watery eyes and runny noses.

Antihistamine can be used to relieve the symptoms of a mild allergic reaction but in a severe reaction anaphylactic shock can occur in which case emergency medical treatment or an injection of epinephrine (adrenaline) as advised by a doctor is required. The best treatment is to steer clear of peanuts if you’re allergic. Although peanuts are not a nut, as we recently found out, if you have a nut allergy you are likely allergic to peanuts too (and visa versa). This is because the allergens are similar so the body responds in the same way.

So that’s a bit about peanuts and nut allergies, but also about some of the benefits of the superfood too. With over 40 million tonnes of shelled peanuts produced worldwide, peanuts are indeed a very popular foodstuff, whether they are a nut or not…

Leave a Reply

Your email address will not be published. Required fields are marked *