Recently, I received a good question from a reader: "Hi, Dr. C! In your book, The Adrenal Reset Diet, you suggest shrimp as a source of protein. I'm confused because I've heard shrimp is a bottom-feeder that contains bacteria, viruses and heavy metals. Should I eat it?"
The short answer is yes, assuming you are not in the 3% of adults or 0.6% of children who are allergic to it.
Foods are complex. Everything you eat has a mixture of things that are good and bad for you. If you simply avoid every food that has any possible bad thing about it, you will have nothing left on your plate.
What is good about shrimp?
Shrimp contains many nutrients we are often lacking, including selenium, copper, choline, zinc, niacin and vitamins B6 and B12. Selenium can be hard to absorb. Some foods or supplements that have it do not prevent selenium deficiencies, yet shrimp raises measured levels of selenium in those who eat it.
Shrimp lowers appetite. It can increase CCK, a hormone from your stomach that stops hunger. Shrimp contains astaxanthin, an antioxidant that helps repair brain cells and muscle tissue. In fact, astaxanthin gives shrimp its pink color. A single serving of shrimp can have up to 4 milligrams of astaxanthin.
Shrimp is a low-calorie source of protein. It is quick to prepare and readily available.
What is bad about shrimp?
Shrimp may contain preservatives. The most common one used to treat shrimp is 4-hexylresorcinol. It is used to prevent bacterial growth from the muscle tissue decay, leading to black spots on shrimp, and may be harmful when used in concentrations over 260 mg/kg. Although 4-hexylresorcinol is commonly found in edible shrimp, its levels range from 1.05 - 1.31 mg/kg, which is far below the dangerous level.
Shrimp can have viruses. White spot syndrome is a newer, viral infection that can wipe out shrimp populations in days. All areas where shrimp are raised are at risk, except Australia. Although this infection can make shrimp production more difficult, the virus has no effect on humans if they ingest shrimp infected with the virus.
Shrimp has arsenic. Arsenic intake is a valid concern, but when seafood contains arsenic, it is a type called arsenobetaine, which is harmless to humans. In fact, studies show this type of arsenic is eliminated through the urine without harming the body at all, even in high amounts.
What should you do?
Enjoy shrimp. Like seafood of all types, be aware of sustainability. Buy it from your local seafood supplier. Domestic, wild, trap-caught shrimp is considered the most sustainable. The Greenpeace report, "Carting Away The Oceans," states the best supermarkets to purchase shrimp include Super Target, Wegmens and Whole Foods.
1 Sicherer, S. Journal of Allergy & Clinical Immunology, July 2004: pp 159-165.
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3 Sandstrom B and Larsen EH. Absorption and retention of selenium from shrimps in man. Journal of Trace Elements in Medicine and Biology, Volume 14, Issue 4, April 2001, Pages 198-204.
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5 Sila A, Ghlissi Z, Kamoun Z, et al. Astaxanthin from shrimp by-products ameliorates nephropathy in diabetic rats. Eur J Nutr. 2014 May 13.
6 INCHEM.org 4-HEXYLRESORCINOL.
7 King JM1, McEvily AJ, Iyengar R.Liquid chromatographic determination of the processing aid 4-hexylresorcinol in shrimp. J Assoc Off Anal Chem. 1991 Nov-Dec;74(6):1003-5.
8 Lightner, D. V. (1996). A handbook of shrimp pathology and diagnostic procedures for diseases of cultured penaeid shrimp. World Aquaculture Society, Baton Rouge, Louisiana, USA.
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11 Found at: http://www.greenpeace.org/usa/Global/usa/report/2010/5/carting-away-the-oceans.pdf.