Peanut Research

The evidence for the role of peanuts and peanut butter as a key food in a healthy diet is mounting. It is clear that incorporating frequent consumption of peanuts, peanut butter and other nuts into our everyday healthy eating habits can have big payoffs in terms of disease risk reduction. Inexpensive, tasty, versatile and nutritious, peanuts are truly one of nature’s original functional foods. 

For information on some of the most frequently asked questions about peanuts, browse through the following topics:

What is considered to be one serving of peanuts or peanut butter?

A serving of peanuts for snacking is considered to be 50 grams, and a serving of peanut butter is 1 tbsp (15 mL).

What nutrients are there in a serving of peanuts or peanut butter?

A serving of dry roasted, unsalted peanuts contains 12 grams of protein, has no sodium or cholesterol, and is:

  • a source of potassium, folate, zinc, vitamin B6, choline, selenium, thiamin, riboflavin, phosphorous and pantothenic acid
  • a good source of vitamin E, copper and magnesium
  • an excellent source of niacin and manganese
  • a high source of fibre

A serving of natural peanut butter contains 4 grams of protein, has no sodium or cholesterol, and is:

  • a source of vitamin E, thiamin, niacin, folate, magnesium, copper and manganese

How do peanuts compare nutritionally to nuts?

All nuts and peanuts contain similar nutrients and have a high proportion of heart-healthy monounsaturated and polyunsaturated fats. Per 50-gram serving: walnuts have the highest omega-3 fat content; almonds have the highest vitamin E and calcium content; and peanuts have the highest folate and niacin content.1 Also, peanuts contain more arginine than many other foods, which can help to open up blood vessels and allow blood to flow better.2,3

Why are peanuts and peanut products good food choices for people who have diabetes?

One key factor for diabetes prevention is healthy eating habits, coupled with weight control and physical activity.

Research from Pennsylvania State University found that those with impaired fasting glucose had improved blood sugar levels in the morning after eating about 1 ounce of peanuts as an evening snack.4

The Nurses’ Health Study which followed almost 84,000 women for 16 years, also found that consuming peanut butter five times per week was associated with a 21% reduced risk of developing type 2 diabetes.5

Peanuts and other legumes can be important sources of fibre, and have a low glycemic index of 15, which is helpful in managing type 2 diabetes.6 In addition, nuts and peanuts have high proportions of unsaturated fat (monounsaturated and polyunsaturated), and offer magnesium and fibre, which all have a beneficial effect on reducing diabetes risk.

Are peanuts gluten-free?

Natural peanuts are gluten-free, but some peanut products, such as peanut butter or dry roasted nuts may contain traces of wheat. If you follow a gluten-free diet, read labels carefully to ensure you’re purchasing only natural peanut products with no wheat-based additives.

How much protein is in a serving of peanuts or peanut butter?

A 50-gram serving of dry roasted peanuts contains 12 grams of protein and a 1-tbsp (15-mL) serving of natural peanut butter contains 4 grams of protein. Nuts and peanuts (which are in fact legumes) are plant-based proteins and fit in the protein foods category as part of a healthy diet in Canada’s food guide.

How can peanuts help with weight management?

To help manage obesity or just to maintain a healthy weight, healthy eating habits, physical activity and sufficient sleep are important. Peanuts can help, too. Peanuts are chock full of protein, fibre and essential vitamins and minerals. They are cholesterol-free and contain mono- and polyunsaturated fats – the good fats that are part of a healthy diet. They help you feel fuller longer than carbohydrate-based foods – making them perfect for snacking.

Should I be concerned about the fat content of peanuts and peanut butter?

Of the fat in peanuts, 85% is the ‘good’ unsaturated fat (about 52% monounsaturated and 33% polyunsaturated). Unsaturated fats are important in heart health as they help to lower blood cholesterol levels. A serving of the vast majority of peanut butters available in Canada is trans-fat-free. Peanuts and peanut butter are naturally cholesterol-free.

Should I be concerned about the amount of sodium in peanuts?

A common misconception is that peanuts and peanut butter are high in sodium. However, a 50-gram serving of unsalted, dry roasted peanuts, as well as a 1-tbsp (15-mL) serving of natural peanut butter, contains only 1-3 mg of sodium, and is considered sodium-free.

Peanut butter also contains much less sodium than people may think – most contains less than 140 mg of sodium per serving and is considered “low in sodium” by the Canadian Food Inspection Agency.

Are peanuts considered heart-healthy?

Around the world, studies have confirmed that regularly eating nuts and peanuts can help reduce the risk of coronary heart disease (CHD). Information from the Practice-based Evidence in Nutrition (PEN, 2019-07-18) confirms that a Portfolio Diet, Mediterranean Diet and DASH Diet (Dietary Approaches to Stop Hypertension) are all recommended to lower LDL-C (Low Density Lipoprotein-C) levels and reduce the risk of cardiovascular disease. Nuts including peanuts are an important component of each of these dietary patterns.

Canada’s McMaster University, site of the largest meta-analysis ever undertaken of the role of diet in heart disease, singled out nuts and vegetables for their strong association with reduced rates of coronary heart disease.7 Researchers at McMaster reported that consumption of 30 g of nuts per day (a small handful), combined with a Mediterranean dietary pattern (fruits, vegetables, whole grains, legumes) led to a 13% reduction of symptoms over one year in a study of 1,224 participants (men, aged 55 to 80 years, and women, aged 60 to 80 years) at high risk of heart disease.8

Furthermore, a Shanghai study of 75,000 middle-aged women aged 34 to 59 years pointed to the link between nut consumption and “a lower risk of coronary heart disease.”5 Another 2009 study that reviewed four large studies totaling over 160,000 men and women showed that eating about 1 ounce of peanuts daily can cut the risk of heart disease in half. This same study found that eating a small handful of peanuts 1 to 2 times per week decreases the risk by over 25%.9

The 2019 Canada’s food guide recommends consuming plant-based protein foods more often. Nuts, such as peanuts, are associated with decreased LDL-cholesterol.10 

Do peanuts grow in Canada?

The Canadian climate isn’t very conducive to growing peanuts, which require sandy soil and warm weather. Peanuts are grown in a few isolated areas in Canada, but demand greatly exceeds supply. As a result, U.S. export statistics for 2023 show shipments of all peanuts and peanut products to Canada at 128,319 metric tonnes.

Are food allergies life-long?

Children commonly outgrow food allergies. However, allergies to peanuts, tree nuts, fish, and crustaceans and molluscs are usually life-long.

If someone is allergic to peanuts, will they be allergic to other tree nuts, and vice versa?

Peanut is a part of the legume family and is not a tree nut; however, while peanuts and tree nuts are different, in some cases people with a tree nut allergy may also react to peanuts. If you have a peanut or tree nut allergy, consult your allergist before eating other tree nuts that are not a regular part of your diet.11

Are there reasons why peanut allergy is so severe?

Peanuts are a complex plant food, with more than 30 different proteins. Research is underway to identify exactly which proteins trigger an allergic reaction, and why the reaction can vary in severity among those with peanut allergy. In Canada, the priority food allergens include egg, milk, soy, tree nuts, peanut, fish, crustaceans and molluscs, sesame, mustard, and wheat and triticale.

Are peanut allergies increasing?

Food allergy is a growing public health issue. Some hypothesize that the lack of early childhood exposure to infectious agents and parasites has increased susceptibility of allergic disease. The lack of early childhood exposure to peanut has also been linked to increased peanut allergy. It’s difficult to determine if the increased reports of peanut allergy are due to actual increases in incidence, or a result of increased awareness among consumers and health professionals.

Can smelling a peanut cause a severe reaction?

No, simply smelling the aroma of peanuts is not the same as breathing in protein particles which may cause an allergic reaction. The chemicals which are detected as the odour of peanuts are aromatic molecules called pyrazines and, alone, are incapable of causing allergic reactions.

How is a severe allergic reaction to peanuts treated?

Epinephrine is the first-line treatment for a severe allergic reaction (anaphylaxis). It helps to slow the progression of the reaction and is more effective if given early.

After administering an epinephrine auto-injector, emergency medical services must then be obtained for further treatment by calling 9-1-1 or local EMS and going to the nearest hospital right away, even if symptoms are mild or have stopped. The reaction could get worse or come back. A second auto-injector should be used as early as 5 minutes after giving the first dose if there is no improvement in symptoms.

Should peanut oil be avoided?

The process of refining oil significantly reduces or, in some cases, removes the protein which would trigger an allergic reaction. Highly refined oil typically does not pose a problem for those with allergies. However, oils which are cold pressed to retain their flavour, or oil that has been used to cook peanuts do contain protein and therefore should be avoided. Before consuming products with highly refined oils, you should discuss with your allergist to determine if these products can be an option for you.

Can anything be done to manage peanut allergy and prevent a reaction?

The only certain way to prevent a reaction is avoidance. With proper management, awareness and education, most reactions to food allergens can be avoided. You can also speak to your allergist about other possible treatments for peanut allergy.

Individuals with food allergy should diligently read all food labels and ask questions about foods prepared away from the home (such as at school or a restaurant). In the day care or school setting, parents of a child with food allergy should inform teachers and school staff, so they are prepared to recognize and treat severe allergic reactions immediately and seek first aid.

In consultation with their physicians, individuals with food allergy and at risk of anaphylaxis should always carry their epinephrine auto-injectors and should also consider wearing an identity bracelet or medallion to alert others that they have food allergy.

How much peanut must be ingested to cause a reaction?

The amount of a food required to cause a reaction varies by person, and in some people, it can be triggered by a small amount.

Can peanut products be made less allergenic by cooking them?

No. A food allergy is an immune system response to a protein in a food. Peanut protein remains in the food during heating, therefore, you cannot make peanut products less allergenic by cooking them.

Where can I learn more about peanut allergies?

Food Allergy Canada's website has a wide variety of resources and tools available, to provide additional, in-depth information about food allergies, including peanut allergies.

When should peanut be introduced to infants and children?

Recommendations for the introduction of common allergens, like peanuts, to infants have changed as research has emerged on ways to help prevent the development of food allergy in babies. A 2021 position statement co-published by the Canadian Paediatric Society (CPS) and the Canadian Society of Allergy and Clinical Immunology (CSACI) includes recommendations on the specific timing of early introduction of allergenic foods for high-risk infants:12

  • Consider infants at high risk for food allergy when they have a personal history of atopy or a first-degree relative (at least one parent or sibling) with an atopic condition (such as asthma, allergic rhinitis, food allergy, or eczema).
  • Promote and support breastfeeding for up to 2 years and beyond, regardless of issues pertaining to food allergy prevention.
  • For high-risk infants, encourage the introduction of allergenic foods (e.g. peanut) early, at about 6 months and not before 4 months of age, in a safe and developmentally appropriate way, at home.
  • In infants at low risk for food allergy, allergenic foods can also be introduced at around 6 months of age.
  • New foods, including commonly allergenic foods, can be introduced on successive days.
  • When allergenic foods have been introduced, make sure that ongoing ingestion of age-appropriate serving sizes is regular (i.e., a few times a week), to maintain tolerance.
  • The texture or size of any complementary food should be age-appropriate to prevent choking. For young infants, smooth peanut butter can be diluted with water or mixed with a previously tolerated pureed fruit or vegetable, or with breast milk. For older infants, smooth peanut butter can be spread lightly on a piece of thin toast, or a peanut puff product could be offered.

The most striking evidence for early introduction of peanut was the Learning Early About Peanut (LEAP) prospective allergy study in the U.K. – the first randomized controlled trial to show that early peanut introduction could help prevent peanut allergy in high-risk infants. In the study, 640 high-risk infants between the ages of 4 to 11 months were randomly assigned to either consume peanut protein at least 3 times per week, or avoid peanuts until they were 5 years old. Findings showed an overall relative risk reduction in peanut allergy of up to 80% with early peanut introduction: the rate of peanut allergy in the group of infants who consumed peanut protein early was 3.2%, compared to 17.2% in the group that avoided peanut protein.13

How should peanut be introduced to young infants?

It is recommended that allergenic foods are fed to an infant, rather than having the baby self-feed (baby-led weaning). This is because food smeared on a baby’s skin may cause skin irritation that can be mistaken for allergy.14

Keep in mind that whole peanuts are a choking hazard and should not be given to children under four years of age. To prepare peanut, stir together 2 tsp of smooth peanut butter with 2-3 tsp of hot water until well blended, then allow to cool. This mixture can be offered alone, or added to an already tolerated infant food, such as infant cereal, pureed fruit or vegetables. Another option is a peanut puff product (e.g., Bamba), which can be softened for younger infants.14

How often should peanut protein be fed to an infant?

Once an infant has eaten peanut protein, and if there is no allergic reaction, it’s very important to keep feeding peanut protein to the baby. It is recommended to feed peanut protein about 2-3 times per week to help prevent the development of a food allergy.14

 Where can I learn more about peanut allergies and early introduction?

Food Allergy Canada is an excellent resource for more information early introduction research and guidelines.

Will my child develop a peanut allergy if I eat peanuts and peanut butter while pregnant and/or breastfeeding?

In general, there is still insufficient evidence to recommend changing a mother’s diet to prevent food allergy (i.e., by avoiding or ingesting particular allergenic foods during pregnancy and while breastfeeding).

Specific to peanut allergy, some studies suggest that mothers who consume peanut while breastfeeding may decrease the risk of peanut sensitization, provided this is done in tandem with the early introduction of peanut protein in the infant’s diet. However, these studies remain insufficient to support a recommendation to actively consume peanut protein during breastfeeding.12

Are organic peanuts available?

Yes, organic peanuts, peanut butter and other peanut products are available.

Are peanuts genetically modified?

No, USA-grown peanuts are not genetically modified.

What are aflatoxins?

Aflatoxins are naturally occurring substances produced by soil-based moulds. Farmers, food manufacturers and the government work together to monitor, regulate and minimize the presence of this mould-based substance in the food supply.

When plants are subjected to severe drought and heat stress, the natural protective mechanisms in the plant breaks down and allows the growth of the moulds that can produce aflatoxins.

How are aflatoxins detected?

Farmers, food manufacturers and government work together to create a web of checks and balances that monitor, regulate and minimize this mould-based substance in the food supply. In the case of peanuts:

  • Farmers work to manage soil-based mould in the field
  • Shellers clean, sort, segregate and test the peanuts after harvest
  • USDA inspects peanuts and issues aflatoxin certifications to shellers
  • Processors and manufacturers sort the peanuts again and often times reclean them; they also blanch the peanuts, which further reduces the possible presence of aflatoxin 

 

Download this PDF with answers to all of the FAQs

Peanut FAQs


References:

  1. Canadian Nutrient File, 2023.
  2. Palmer, R.M., Ashton, D.S., Moncada, S. Vascular endothelial cells synthesize nitric oxide from L-arginine. Nature 1998; 333:664-6.
  3. Huynh, N.N., Chin-Dusting, J. Amino Acids, Arginase and Nitric Oxide in Vascular Health. Clinical and Experimental Pharmacology and Physiology 2006; 33(1-2):1-8.
  4. Sapp, P. et al. Fasting glucose response to evening snacks that differ by carbohydrate and fat consumption: A 6-week, randomized, crossover trial in subjects with impaired fasting glucose. Current Developments in Nutrition 2020; 4(Supp 2): 1143.
  5. Jiang, R., et al. Nut and peanut butter consumption and risk of type 2 diabetes in women. Journal of the American Medical Association 2002; 288(20):2554-2560.
  6. Jenkins, D., et al. Starchy Foods and Glycemic Index. Diabetes Care 1988; 11:2-149.
  7. Mente, A., et al. A Systematic review of the evidence supporting a causal link between dietary factors and coronary heart disease. Archives of Internal Medicine 2009; 169(7):659-669.
  8. Salas-Salvado, J., et al. Effect of a Mediterranean diet supplemented with nuts on metabolic syndrome status: one year results of the PREDIMED randomized trial. Archives of Internal Medicine 2008; 168(22):2449-2458.
  9. Sabate, J., et al. Nuts and health outcomes: new epidemiologic evidence. American Journal of Clinical Nutrition 2009; 89 (suppl):1S-6S.
  10. Canada’s Dietary Guidelines for Health Professionals and Policy Makers, Health Canada, 2019.
  11. Health Canada. Tree Nuts: Priority food allergens 2017. https://www.canada.ca/content/dam/hc-sc/documents/services/food-nutrition/reports-publications/foodsafety/2017-treenuts-noix-eng.pdf
  12. Abrams, E., Orkin, J., Cummings, C., Blair, B., Chan, E., Canadian Paediatric Society. Dietary exposures and allergy prevention in high-risk infants. Paediatrics & Child Health. 17 December 2021. https://cps.ca/en/documents/position/dietary-exposures-and-allergy-prevention
  13. Du Toit, G., et al. Randomized Trial of Peanut Consumption in Infants at Risk for Peanut Allergy. N Engl J Med 2015; 372:803-813.
  14. Food Allergy Canada & Canadian Society of Allergy and Clinical Immunology. Eat Early. Eat Often. https://foodallergycanada.ca/wp-content/uploads/Eat-Early-Eat-Often.pdf