They may not always look so appealing, but fish is one of nature’s most nutritious foods. Some fish are better for you than others, but the oily kinds are the ones you should focus on for the most health benefits. Their heart-healthy fats are spread out through their flesh instead of being concentrated in the liver like they are in white fish. Oily fish like trout, salmon, sardines, and mackerel are full of fatty acids that are good for your heart, like Omega-3. They are also a great way to get vitamins A, D, E, and K, which are fat-soluble.
There are many places in the world that are healthier because people eat a lot of fish. Japan has one of the longest life expectancies in the world. This is because Japan is an island country that has always relied on the sea for food. The Eskimo people of Greenland eat a lot of fish every day, so they have fewer heart diseases, strokes, and high blood pressure than people around the world.
Even though it’s clear that a diet high in fish is good for you, some people may find it hard to get these benefits. It’s possible for some people to get sick after eating fish, which makes them avoid the food and its health benefits. A bad reaction to fish could be caused by fish allergy or fish intolerance. Both of these conditions can be very painful, but it’s easy to be confused or even doubtful about whether you have a fish intolerance or allergy, especially if you don’t know the symptoms. So you can tell the difference between the two, we’ve put together a list of the causes, symptoms, and treatments of fish intolerance and fish allergy.
Salmon is often recommended as one of the healthiest fish you can eat. It’s full of omega-3 fatty acids, high-quality proteins, vitamins, and minerals. However, some people experience nausea or other unpleasant symptoms after eating salmon.
If you’ve ever felt sick to your stomach after a salmon meal, you may be wondering why this fish that’s so good for you can make you feel so bad. Here are the most common reasons salmon could be causing nausea and how to avoid it
Food Poisoning
Food poisoning is one of the most likely reasons why people feel sick after eating salmon. There are two main types of food poisoning you can get from fish:
- Ciguatera poisoning – From reef fish living in tropical areas
- Scombroid poisoning – From fish not stored properly after catching
When salmon is poisoned by scombroids, bacteria on the fish make histamine as the fish goes bad. Common symptoms include:
- Nausea
- Vomiting
- Diarrhea
- Abdominal cramps
- Headache
- Rash
- Itching
Ciguatera poisoning comes from toxins produced by algae that reef fish ingest. Symptoms often start with digestive upset like:
- Nausea
- Vomiting
- Diarrhea
And progress to neurological symptoms like:
- Headache
- Muscle aches
- Tingling or numbness in hands and feet
To avoid food poisoning, only buy salmon from reputable sellers, stores, and restaurants. Check expiration dates and don’t eat salmon that smells fishy or bad.
Allergic Reaction
Up to 2% of adults have a fish allergy, which can cause nausea after eating salmon. This is caused by your immune system overreacting to parvalbumin, a protein abundant in fish.
Allergic reactions usually appear quickly after consuming fish Symptoms may include
- Hives or rash
- Swelling of the face, lips or throat
- Tingling in the mouth
- Abdominal pain, nausea, vomiting
- Diarrhea
- Wheezing or difficulty breathing
If you have a salmon allergy, your best bet is to avoid it altogether. Antihistamines can help mild symptoms, but severe allergic reactions require an epinephrine injection.
Mercury Poisoning
Mercury is a heavy metal that gets into waterways and accumulates in fish over their lifespan. Older, larger fish at the top of the food chain have higher mercury levels.
Consuming salmon and other fish high in mercury over time can cause mercury poisoning. Symptoms include:
- Nausea
- Vomiting
- Abdominal cramps
- Diarrhea
- Headaches
- Fatigue
- Tingling in hands and feet
Choose young, wild salmon over older farmed varieties to avoid excessive mercury exposure. Limit consumption to 2-3 servings per week.
Histamine Intolerance
Some people lack enough of the enzyme diamine oxidase (DAO) needed to properly metabolize histamine in fish. Salmon has higher histamine levels than other fish.
With histamine intolerance, symptoms like nausea, vomiting and diarrhea can appear rapidly after eating fish. Other symptoms may include:
- Hives or rash
- Headache
- Flushing
- Itching
- Asthma-like wheezing
Taking a DAO enzyme supplement before consuming fish high in histamine like salmon can help improve tolerance and prevent a reaction.
Fat Content
The high fat content of salmon could also trigger nausea in some people unused to eating very fatty foods. Salmon has about 5-8 grams of fat per 3 ounce serving.
Eating smaller portions of salmon or choosing leaner preparations like grilled salmon instead of fried can help minimize nausea from the fat.
How to Prevent Salmon Nausea
Now that you know why salmon can cause nausea for some people, here are some tips to help prevent it:
- Purchase salmon from reputable sellers and check expiration dates
- Cook salmon thoroughly to at least 145°F internal temperature
- Start with small portion sizes if you have sensitivity to fat
- Avoid salmon roe, sushi, or other raw preparations
- Take DAO enzyme supplement if you have histamine intolerance
- Opt for younger wild salmon vs farmed if concerned about mercury
While salmon is very healthy overall, it’s not for everyone. Paying attention to sourcing, storage, preparation and your personal tolerance can help you enjoy salmon without the nasty nausea.
What is a fish intolerance?
An intolerance isn’t always necessarily something a person will have for life. It’s common for someone to eat fish without any problems for years and then find that it makes them sick all of a sudden.
However, unlike allergies, a fish intolerance only happens when the fish is eaten, not just handled, and an immune response happens. This means that a person may find that eating one type of fish doesn’t hurt their health, but eating another type of fish makes them sick; salmon may be fine, but tuna may not be.
Symptoms of a fish allergy usually show up soon after eating the food that causes the allergy, but symptoms of a fish intolerance can take anywhere from a few hours to a few days. This can make it easy for people who are trying to self-diagnose to blame the wrong food.
What are the symptoms of fish allergy?
Like most allergies, fish allergy symptoms differ in severity from person to person. A mix of symptoms is common, but some people may only show one of the obvious ones. These are the known symptoms:
- Skin rash
- Headaches
- Runny nose sneezing
- Nausea
- Stomach cramps
- Diarrhoea
- Anaphylaxis – can cause impaired breathing, and be life threatening.
As mentioned above, fish allergy symptoms can be life-threatening, so if you are having any of these issues and think fish may be the cause, you should see a doctor right away.
Mercury Fish: Eating Salmon Is NOT an Issue – Dr. Berg
FAQ
Can salmon upset your stomach?
Why do I feel weird when I eat salmon?
Why do fish make me feel sick?
Can you be allergic to cooked salmon but not raw?
Does salmon make you feel dizzy?
To determine whether you have it, the best thing to do is get yourself tested for allergies. A few Redditors had another theory: salmon is very fatty and could make you feel dizzy if you don’t eat oily foods as much. In a way, it makes sense. Lately, I haven’t been eating fatty meat or oily seafood more than once per week.
Can eating salmon cause constipation?
No, eating salmon does not typically cause constipation. Salmon is protein source that contains healthy fats that can be included as a part of a balanced, healthy diet.
What happens if you eat salmon?
In severe cases, a person can go into anaphylactic shock when he consumes salmon or other finned fish. Symptoms produced by this type of allergic reaction include chest tightness, shortness of breathe and a choking sensation. The person may lose consciousness and suffer a quick drop in blood pressure.
Can you get sick if you eat salmon?
If you become sick after eating salmon and suffer from upset stomach, vomiting or nausea, it does not necessarily mean that you have a salmon allergy. Food poisoning can produce similar symptoms to a seafood allergy and can occur when a person consumes spoiled salmon. Find your way to better health.