What happens if you eat rancid nuts?

In this brief guide, we will answer the query, “What happens if you eat rancid nuts?” and will discuss how to tell if nuts have gone rancid.

What happens if you eat rancid nuts?

Eating rancid nuts can cause digestion problems and other health problems, because lipid oxidation generates potentially toxic products that have shown correlation with inflammatory diseases, as well as cancer, atherosclerosis and aging (3). Even if you don’t become ill right away from eating rotten or stale nuts like almonds, walnuts, or cashews, it’s typically not a good idea since it might interfere with digestion or have other negative consequences on your health over the long run.

What are nuts and how are they helpful?

Among all of nature’s wealth, nuts are among the most cherished. Including them in your regular diet is the best way to stay healthy. Snacks are excellent, but they may also be utilized in desserts and a wide variety of sweet and savory foods. 

To maintain a healthy diet and lifestyle, you need to stock up on crunchy items in your cupboard. As a source of good fats, nuts protect your heart by reducing the levels of bad cholesterol (LDL) in your blood, which lowers your risk of heart disease. The most popular tree nuts globally include almond, Brazil nut, cashew, hazelnut, macadamia, pecan, pine nut, pistachio and walnut (1) and an annual global trade in excess of $US32 billion (2).

 Nuts are high in protein and fiber and may help curb hunger. In general, these foods contain healthy monounsaturated (MUFA) and polyunsaturated (PUFA) fatty acid profiles; soluble and insoluble fibers; vitamins E and K; folate; thiamine; minerals such as magnesium, copper, potassium, and selenium; and substances such as zanthophyll carotenoids, antioxidants, and phytosterols compounds, with recognized benefits to human health (1). Nuts may also help regulate mood and improve mental sharpness, according to several studies. As a result, becoming friends with nuts is a wise decision.

There is nothing better than the flavor of nuts! No matter whether you like them roasted or raw, these small delicious packets are sure to please your taste buds. 

To make nut butter, they may be processed into spreads for sandwiches and dairy butter substitutes. The unsaturated fats in nuts are what make them nutritious, but they are also what makes them perishable. 

For a longer amount of time, nuts are more stable than our fresh fruits and vegetables, although they are vulnerable to rancidity. When the oil in nuts oxidizes, the result is rancidity.

How to Identify and Prevent Nut Rancidity?

Nuts have a high oil content and fatty acid composition that can render them susceptible to oxidative rancidity and rapid deterioration (2). Rancid or stale nuts such as almonds, walnuts, or cashews may not make you ill right away, but it’s typically not recommended since it may cause digestive problems or other long-term damage to your health. Lipid oxidation also produces secondary products, such as carbonyl compounds, malonaldehyde, other aldehydes, hydrocarbons, ketones and furans, that are indicators of food quality deterioration. these compounds are volatile and can be identified through typical odor (2). 

Baked goods made with these nuts will taste bitter and sour if you use them. This is why you need a good sense of smell and two simple techniques to tell whether your nuts are rotten or stale.

The best way to keep nuts fresh for as long as possible is to store them in airtight containers in a cool, dry environment. Nutty wafts fill the air as soon as a package of high-quality nuts is unwrapped. 

Paint or nail polish may come to mind when you think of rancid nuts because of their distinct fragrance. Rancid nuts, according to some, have an odor reminiscent of stale plastic containers. If you detect any of these odors in your nut container, it’s best to toss them.


Rancidity of oils produces undesirable volatile compounds and off-flavours (2).

As a last resort, you might conduct a taste test to establish whether or not your nuts have gone rancid. Take a bite of your nut after breaking off a little chunk. You won’t be able to stand the smell or flavor of the nut.

Rancid nuts have a sour or bitter flavor that is unpleasant. Spit them out and throw away the rest of the stock if that is the flavor of your nuts.

Stale or rotten nuts have a strange odor and flavor

To prevent the oxidation of lipids in your nuts, immediately move them from their packing to airtight containers. If kept properly, most nuts may survive for three to six months. If you reside in a warm region, another option is to keep your nuts in the refrigerator.

What happens if you eat rancid nuts?

Even if you consume rotten nuts, you are unlikely to have any negative consequences other than a bad taste in your mouth. Although rancid nuts might cause stomach and intestinal discomfort, nausea, vomiting, or diarrhea may occur in rare circumstances. 

This may have a long-term impact on health since rancid oils in nut butter may induce inflammation and carcinogens. Eating rotten or infected nuts might worsen symptoms immediately away in a few uncommon instances. The ingestion of oxidized fats leads to the formation of lipid oxidation aldehydes, which are potentially toxic and highly reactive with proteins, phospholipids, and nucleic acids and can be transported into the cell and tissues. Thesel might have health implications by promoting gut inflammation and possibly altering the microbiome (3).

If you have bloody vomiting or diarrhea, severe discomfort or stomach cramping, a temperature above 101.5 degrees Fahrenheit, difficulty speaking or swallowing, double vision, or muscular weakness that travels down your body, you should get medical assistance right once. You should consume water or sports drinks if you are dehydrated..

How to store nuts so they last longer?

Storage conditions, such as humidity, light incidence, oxygen concentration and temperature strongly determine the shelf life of nuts (2). Storage of kernels with their skin (testa) on also reduces oxidative rancidity as the skin or testa acts as an oxygen barrier, minimising lipid oxidation. The use of packages with high humidity, light and oxygen barriers are useful, as well as low temperatures for the storage (2). If you’re concerned about nuts going bad, it’s better to buy smaller quantities rather than bulky sacks. 

Ideal storage conditions for tree nuts are generally low temperatures (from 4 to 15°C), low moisture content (around 2.5%), low relative humidity (40–60%), low oxygen concentration (< 2.5%) and dark conditions (2). The optimal place is inside of a refrigerator. Shelled nuts may be stored in the refrigerator for six months and in the freezer for up to a year. Nuts that haven’t been shelled may last up to two years.


In this brief guide, we answered the query, “What happens if you eat rancid nuts?” and discussed how to tell if nuts have gone rancid.


  1. De Souza, Rávila Graziany Machado, et al. Nuts and human health outcomes: a systematic review. Nutrients, 2017, 9, 1311.
  2. Gama, Tsvakai, et al. Quality and shelf life of tree nuts: A review. Sci hortic, 2018, 242, 116-126.
  3. Vieira, Samantha A., Guodong Zhang, and Eric A. Decker. Biological implications of lipid oxidation products. J. Am. Oil Chem.’ Soc., 2017, 94, 339-351.