Unlike sweet almonds, bitter almonds contain glycoside amygdalin. When ingested, this substance breaks down into hydrogen cyanide, which is a deadly toxin.
Almonds are one of the most popular tree nuts worldwide. They’re nutritious and generally thought to benefit your health.
That said, certain varieties are known to increase the likelihood of food poisoning, digestive troubles, and potentially even your risk of diseases like cancer. Others are, in fact, poisonous and ultimately unfit for human consumption.
This article reviews the different types of almonds, which ones are considered safe to eat, and which ones are best avoided.
Almonds can be divided into two major species that are very similar genetically — bitter almonds and sweet almonds.
Sweet almonds have a slightly nutty flavor and are the ones you typically find on your supermarket shelves or in almond-based products, such as nougat or marzipan.
As their name implies, bitter almonds have a very bitter flavor. This type grows both in the wild and commercial settings and is mainly used to make bitter almond pastes or extracts. They’re not typically found in grocery stores.
Bitter almonds were the most common species grown until a few thousand years ago when a genetic mutation inhibited the almond tree’s ability to make amygdalin — the compound that gives bitter almonds their bitter taste (1).
This mutation is what gave rise to sweet almonds and allowed the domestication of the almond tree that we know today.
Rancid oil makes the stale almonds taste bad. Spoiled almonds aren’t poisonous, but the fats are no longer beneficial. It is possible that rancid fat could contribute to chronic health problems if consumed often. 3 So when the almonds taste bad, it’s time to throw them out.
Raw bitter almonds are poisonous
Bitter almonds contain a toxin known as glycoside amygdalin. When eaten, this toxin gets broken down into several compounds, including hydrogen cyanide — a toxic compound that can cause death (2, 3).
Case studies suggest that swallowing 6–10 raw bitter almonds is sufficient to cause serious poisoning in the average adult, while ingesting 50 or more can cause death. Smaller numbers are likely to have the same harmful effects in children or young adults (4).
Interestingly, hydrogen cyanide appears to leach out of the almonds during heat processing. For instance, baking, microwaving, and boiling reduces the cyanide content of bitter almonds by 79%, 87%, and 98%, respectively (5).
However, more studies are needed to confirm these findings, as well as to determine the exact amount of heat-processed bitter almonds that’s considered safe to eat.
Until more is known, bitter almonds are best avoided.
What are the potential health risks of consuming expired almonds?
FAQ
What happens if I eat expired almonds?
What happens if you eat bad almonds?
What happens if you eat expired nuts?
How do you know if almonds are bad?
What happens if you eat expired almonds?
Consuming expired almonds can result in potential health risks. Although almonds have a relatively long shelf life, their natural oils may become rancid over time when stored improperly, leading to an off smell and taste. Rancid nuts may contain harmful free radicals.
What are the side effects of having excess almonds?
In several studies almonds are shown to reduce LDL cholesterol which is a known risk factor for cardiovascular diseases. Almonds are rich in vitamin E, riboflavin, niacin, B6, folate and potassium. They also contain substantial dietary fiber, monounsaturated fats, polyunsaturated fats and phytosterols. Oxalate is a metabolite consumed in nuts, oxalosis can cause nephropathy and irritable bowel syndrome. Hence anything in excess is not recommended.
Can almonds make you sick?
If you are hesitant about eating almonds that may or may not be past their prime, you should remember that if you do eat almonds that have become rancid and have a very bitter or sour taste, they can make you sick. In fact, if you consume as few as six almonds that taste very bitter, you can suffer from mild levels of cyanide poisoning.
Do almonds have an expiration date?
They do have an expiration date. However, almonds may still be safe to eat after this date if they have been stored properly and do not show signs of spoilage such as a rancid smell or taste. How can you tell if almonds are rancid or stale? Smell and taste test: A sour or bitter smell and taste often indicate that almonds have gone rancid.