You love the taste of juicy shrimp but dread the nausea that often follows. If shellfish like shrimp, lobster or crab leave you queasy, you’re not alone. Approximately 2% of adults report being allergic to shellfish, which can trigger digestive distress in addition to other unpleasant symptoms.
But an allergy isn’t the only reason shrimp can flip your stomach. Here are some common culprits behind shrimp-induced nausea, and tips to help avoid it.
Shellfish Allergy
A shellfish allergy is one of the most likely reasons eating shrimp makes you feel nauseated or unwell. Some signs of shellfish allergy include:
- Hives, itchy skin, or swelling of the face, lips, tongue and throat
- Wheezing, trouble breathing, coughing, or throat tightness
- Vomiting, abdominal pain, nausea, and diarrhea
- Dizziness, fainting, or lightheadedness
If you experience any of those severe reactions after eating shellfish you should see an allergist for testing. They can diagnose a shellfish allergy through a simple skin prick test.
Once diagnosed the only way to prevent symptoms is strictly avoiding all shellfish, even trace amounts. Carry emergency epinephrine if your reactions are severe.
Iodine Sensitivity
Some people mistakenly think being allergic to shellfish means they’ll react to radiocontrast dye or iodine. However, the two are unrelated.
Shellfish happens to contain small amounts of iodine, but it’s a different form than what’s used in medical imaging and iodine supplements. People with shellfish allergies can typically tolerate both.
However, a very small subset of people may have an unusual sensitivity specifically to iodine itself. Consuming high-iodine foods like shrimp can make them feel unwell or nauseated.
If you suspect iodine is the culprit, talk to your doctor about being tested for iodine sensitivity or intolerance. Avoiding iodine-rich foods may be recommended.
Food Poisoning
Consuming contaminated, spoiled, or undercooked shellfish can result in foodborne illnesses that cause nausea and other gastrointestinal symptoms like:
- Vomiting
- Diarrhea
- Abdominal cramping
- Fever
- Chills
- Headaches
Food poisoning from shrimp or other shellfish typically comes on fast, within hours of consumption. It resolves within 1-3 days.
To prevent food poisoning, only eat shellfish from reputable restaurants or retailers. Store and handle raw shrimp properly at home, cooking thoroughly before eating.
High Levels of Cholesterol
Shrimp contain high amounts of dietary cholesterol compared to other proteins, providing over 100mg per 3 oz serving. In sensitive individuals, this may trigger nausea or stomach upset.
Those managing high blood cholesterol levels may need to limit intake of cholesterol-rich foods like shrimp. But for most people, dietary cholesterol has little impact on blood cholesterol.
If you find shrimp disagrees with your stomach despite having normal cholesterol levels, simple cholesterol sensitivity could be to blame.
Heavy Metals
Some types of seafood are prone to absorbing heavy metals like mercury, lead, cadmium, and arsenic from water sources. The levels are generally too low to cause acute poisoning.
However, sensitive individuals who eat a lot of contaminated seafood over time may experience nausea, vomiting, and diarrhea as milder symptoms of heavy metal toxicity.
To reduce this risk, opt for small, short-lived shrimp and prawn varieties which tend to have lower heavy metal bioaccumulation.
Histamine Intolerance
Shrimp naturally contain high levels of the compound histamine. In healthy people, the enzyme diamine oxidase breaks down excess histamine.
But some lack sufficient diamine oxidase activity, allowing histamine to build up. Too much triggers nausea, headaches, hives, and other symptoms.
If histamine foods like aged cheese, wine, or shrimp consistently make you feel ill, ask your doctor about getting tested for histamine intolerance. Avoiding trigger foods can help.
Acid Reflux or GERD
For those with gastrointestinal conditions like acid reflux or gastroesophageal reflux disease (GERD), shrimp can aggravate symptoms. Common triggers include:
- High fat content, which causes digestion issues
- Spicy seasonings like Cajun or Creole flavors
- Onions, garlic, or other foods shrimp is cooked with
Sticking to low-fat preparations of shrimp and avoiding spicy accompaniments or triggers can help minimize reflux and nausea.
Premenstrual Hormone Changes
Some women experience nausea, bloating, and stomach upset around their menstrual cycles due to hormonal fluctuations. Consuming high-cholesterol foods like shrimp during this time may worsen symptoms.
Keeping a symptom journal can help identify if there is a cyclical pattern. Avoiding triggers like shellfish during PMS windows may help relieve monthly nausea.
Tips for Preventing Shrimp-Induced Nausea
Here are some general tips for lessening the chances that shrimp will leave you feeling queasy:
- Stick to small portion sizes of 3 oz or less per meal
- Choose low-fat cooking methods like grilling or baking instead of frying
- Avoid dunking shrimp in high-fat sauces and dressings
- Skip the cocktail sauce, which contains nausea triggers like ketchup and horseradish
- Take an anti-nausea medication like Pepto-Bismol when consuming shrimp
- Purchase wild-caught American shrimp when possible
- Clean and devein shrimp thoroughly to remove bacteria
- Don’t overcook shrimp, which makes them rubbery and unappetizing
While shrimp can be a tasty source of protein, clearly they don’t agree with everyone. Pay attention to how your body responds and avoid potential triggers to keep mealtimes pleasant.
When to See a Doctor
Make an appointment with your doctor or allergist if:
- You experience signs of anaphylaxis like throat swelling, trouble breathing, or fainting
- Nausea and vomiting persist over several hours after eating shrimp
- Symptoms are severe and recurring each time you eat shellfish
Diagnostic testing can help identify whether an allergy, intolerance, or other issue is causing your negative reaction to shrimp. Proper treatment will have you enjoying your favorite seafood worry-free once again.
References:
[1] https://www.mayoclinic.org/diseases-conditions/shellfish-allergy/symptoms-causes/syc-20377503
[2] https://www.reddit.com/r/Cooking/comments/pcxr25/how_come_eating_shrimp_always_causes_me_pain/
Symptoms of Shellfish Allergies
FAQ
Can shrimp make you feel sick?
Why does my stomach get upset when I eat shrimp?
Why do I get nauseous after eating seafood?
Why do I get a weird feeling in my throat after eating shrimp?
What happens if you eat shrimp?
The toxins in the shrimp also might cause you to have problems swallowing or talking. Food poisoning also can cause blood in the stool, as well as problems with your sight, including double vision or blurred vision. Symptoms of shrimp food poisoning could emerge anywhere from a half hour to several days after you eat contaminated shrimp.
What are the causes of feeling nauseous?
Causes of feeling nauseous – Seasickness and other motion sicknesses. Early pregnancy. Intense pain. Exposure to chemical toxins. Emotional stress (fear) Gallbladder disease. Food poisoning. Indigestion.
Can shrimp cause food poisoning?
Otherwise, a key to getting better involves keeping yourself hydrated by drinking water and other liquids to replenish the fluids and electrolytes you have lost because of the illness. Food poisoning caused by shrimp often can be avoided. Here are some tips: Quickly refrigerate any shrimp you do not plan to eat immediately.
How do you know if you have shrimp food poisoning?
In general, however, additional signs of shrimp food poisoning include dizziness, stomachache and muscle weakness. You could experience paralysis, tremor or a numb sensation in the lips, tongue, arms or legs. The toxins in the shrimp also might cause you to have problems swallowing or talking.