Why Cashews Are Not Good for You

Medically Reviewed on 6/24/2022
While cashews are fine if consumed in moderation, they aren’t always good for you

Cashews are protein-packed nuts that are a good source of vitamins, minerals, fiber, and antioxidants. For most people, consuming them in moderation is fine. But it’s important to be aware of what makes cashews not so great for some.

Nut allergies

Cashew allergy is one of the most common nut allergies in the U.S. And if you are allergic to any tree nut, chances are you may also be allergic to cashews. Check with your doctor before munching on cashews.

High oxalate content

Cashews have a fairly high oxalate content, and eating foods with a lot of oxalates can cause kidney stones. So it’s important to keep an eye on how many cashews you’re eating. More than an ounce a day may be too much. Eating them with milk may help since calcium can help reduce oxalate absorption. 

If you have kidney stones or are at risk for kidney-related conditions, you should talk to your doctor about how much is safe to eat.

Raw cashews are unsafe

Raw cashews with shells contain a chemical called urushiol, which is poisonous. This toxic substance can seep into the cashew as well. Removing the shells from raw cashews and roasting them destroys urushiol. So opt for roasted cashews when you’re at the store since they are safer to eat.

If you are trying to lose weight or have high blood pressure, stay away from salted cashews.

How many cashews can you eat in a day?

The nutty and creamy flavor of cashews can be tempting, and it’s easy to end up consuming too much in one sitting.

Try to consume no more than one ounce (28.35 grams) of medium cashew a day to reap health benefits. A single serving of cashews contains about 18 nuts. One way to keep your intake under control is to pack them in small, single-serving containers or bags.

What is the nutritional value of cashews?

Table. The nutritional content of cashews (1-ounce serving)
Nutrient Quantity
Total carbohydrates 8.56 grams
Fiber 0.94 grams
Protein 5.16 grams
Total fats 12.4 grams
Cholesterol 0
Calcium 10.5 mg
Iron 1.89 mg
Magnesium 82.8 mg
Phosphorous 168 mg
Potassium 187 mg
Sodium 3.4 mg
Zinc 1.64 mg
Copper 0.62 mg
Selenium 5.64 µg
Vitamin C 0.14 mg
Thiamin 0.12 mg
Riboflavin 0.02 mg
Niacin 0.30 mg
Pantothenic acid 0.25 mg
Vitamin B6 0.12 mg
Folate 7.09 µg
Lutein + Zeaxanthin 6.24 µg
Vitamin E 0.26 mg
Vitamin K 9.67 µg


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9 health benefits of cashews

Nine health benefits of cashews include:

  1. Help maintain heart health: Cashew provides good fats and antioxidants that help manage blood pressure and cholesterol levels and keep the heart-healthy.
  2. Good for the muscles and bones: Cashews are a rich source of protein, calcium, phosphorous, magnesium, and vitamin K. These nutrients promote healthy bone and muscles.
  3. Great for healthy skin and hair: The B vitamins, vitamin E, protein, and antioxidants nourish your skin and hair from within.
  4. Promote healthy vision: Antioxidants such as selenium, lutein, zeaxanthin, and vitamin C protect the eyes from harmful free radicals.
  5. May help with weight management: Cashews are quite filling because they are protein-rich and contain fiber. They may help boost metabolism, curb appetite, and facilitate weight loss.
  6. Help manage blood sugar levels: Cashews are good for people with diabetes. They help manage blood cholesterol and sugar levels. Some studies report that they may help lower insulin resistance.
  7. Good for the brain and nerves: Unsaturated fats in cashews help improve brain health. They may play a role in improving memory. Additionally, cashews contain B vitamins and antioxidants that help protect the nerves and brain.
  8. Good for the gut: Fiber and polyphenols in cashew aid in digestion and promote gut immunity.
  9. Fight oxidative stress: Oxidative stress has been linked with inflammation and various chronic conditions including allergies, metabolic syndrome, and cardiovascular diseases. Cashews help lower oxidative stress and may play a protective role against these conditions.

Are there any risks of eating cashews?

Although rich in nutrients, it is advisable to consume cashews in moderation. A large number of cashews must particularly be avoided by pregnant and breastfeeding women and people with diabetes.

Consuming cashews in excess may cause an increase in blood sugar levels. Thus, they must be avoided in a large amount at least two weeks before a planned surgery. Raw cashews contain a poisonous substance called urushiol. It is thus advised to consume cashews after removing their shells and roasting them. Avoid fried or salted cashews to prevent excess calories and sodium consumption.

Some of the downsides associated with cashews include:

  • High in calories: Cashews are high in calories. There is a higher likelihood of eating them in excess because they are delicious. This can cause problems such as obesity, high blood lipids, and sugar levels. 
  • May contribute to heartburn: Although not directly related, fatty foods such as nuts can lead to heartburn, particularly when eaten in excess.
  • May cause allergies: Some people are allergic to tree nuts such as cashews. If you develop any discomfort after eating cashews or other tree nuts such as itching, hives, or difficulty swallowing or breathing, consult your doctor.
  • Can cause drug interactions: You must particularly avoid cashews in excess if you are on antidiabetic medications. Cashews can lower the effect of these drugs, including insulin, and cause problems with blood sugar control.

Are cashews good for PCOS?

Here are 4 reasons why patients suffering from PCOS should add cashew nuts to their diet.

Most studies and researchers believe that cashews are beneficial to patients suffering from polycystic ovary syndrome (PCOS).

Here are 4 reasons why patients suffering from PCOS should add cashew nuts to their diet:

  1. Healthy snack option:
    • Patients with polycystic ovary syndrome (PCOS) have a limited snack selection because they tend to bloat or get gastric issues more frequently. 
    • Cashews are thought to be one of the healthiest snack options for them. 
    • Snack on foods that have a low glycemic index and keep them on hand for when you need them.
  2. Cashew nuts are loaded with magnesium:
    • Magnesium is an essential cofactor in over 300 enzymatic processes in the body. It is necessary for hormone metabolism and helps maintain hormonal balance.
    • According to research, maintaining optimal magnesium levels may improve insulin resistance in PCOS.
  3. Cashews are healthy protein, carbohydrate, and fat:
    • Insulin resistance and dysregulated blood sugar (even in those who are not overweight) are frequently at the root of PCOS-related symptoms, and eating protein with carbohydrate and protein sources, such as cashew nuts, can help blunt the insulin response.
    • Cashew nuts are a good source of omega-3 fatty acids, which patients with PCOS should consume regularly.
  4. Rich in iron:
    • Women with PCOS who experience heavy bleeding may suffer from iron deficiency, so it is recommended that they include iron-rich foods in their diet
    • Iron helps increase hemoglobin, which transports oxygen throughout the body, thus reducing PCOS fatigue and mood swings.
    • Cashews are thought to be a good source of iron.

Nuts and seeds are high in protein, fiber, antioxidants, vitamins, and minerals, which are all beneficial to PCOS symptoms.

  • These contain some healthy fats, which can have an anti-inflammatory effect, as well as provide a healthy structure to cells.
  • Minerals, such as magnesium, zinc, and calcium, are abundant in many nuts and seeds.
  • A serving of nuts or seeds per day can help your body in a variety of ways.

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Medically Reviewed on 6/24/2022
Image Source: iStock image

Bernardino M, Parmar MS. Oxalate nephropathy from cashew nut intake. CMAJ. 2017;189(10):E405-E408.

Nutrition: Nuts & Heart Health. https://my.clevelandclinic.org/health/drugs/17283-nutrition-nuts--heart-health

Nuts, cashew nuts, raw. https://fdc.nal.usda.gov/fdc-app.html#/food-details/170162/nutrients

WebMD. PCOS (Polycystic Ovary Syndrome). https://www.webmd.com/women/what-is-pcos

The Office on Women's Health. Polycystic ovary syndrome. https://www.womenshealth.gov/a-z-topics/polycystic-ovary-syndrome

National Institutes of Health. Polycystic Ovary Syndrome (PCOS). https://www.nichd.nih.gov/health/topics/pcos

Endocrine Society. Polycystic Ovary Syndrome (PCOS). https://www.hormone.org/diseases-and-conditions/polycystic-ovary-syndrome

Centers for Disease Control and Prevention. PCOS (Polycystic Ovary Syndrome) and Diabetes. https://www.cdc.gov/diabetes/basics/pcos.html