We should be eating fish at least twice a week for optimal health. With growing concerns about toxins in the oceans, it's good to know that sardines are the safest choice of fish to eat.
The fish boasts a wealth of nutrients, such as omega-3 fatty acids that contribute to sardines' health benefits, such as reduced inflammation and better bone health.
What Are Sardines?
Sardines, also referred to as pilchard or herring, are a type of small, silver-colored, oily fish that belongs to the Clupeidae family. Sardines were originally found in great abundance around the island of Sardinia, and now they thrive all over the world in the Mediterranean, Atlantic and Pacific oceans.
Sardines are larger than anchovies and can grow up to 12 inches in length. The flesh of sardines is white, and the fish has a slightly protruding lower jaw.
Sardines contain 191 calories per 3.75-ounce can, weighing 92 grams, per the USDA. The caloric ratio is split 50/50 with fats and protein.
Supplying 45 percent of your daily value (DV), a can of sardines is a good source of protein that provides the resources needed for the healthy functioning of your body.
Of the total fat content — 10.5 grams — sardines contain mostly mono- and polyunsaturated fats, which include healthy omega-3 fatty acids. Sardines do not contain any carbohydrates.
The Health Benefits of Sardines
1. They're Packed With Vitamins
Sardines' nutrition includes B vitamins that help turn the food you eat into energy for the proper functioning of the heart, nerves, brain, muscles and blood cells. Each 3.75 ounce can of sardines contain most of the B vitamins, including:
- Vitamin B12: 343 percent DV
- Niacin: 30 percent DV
- Riboflavin: 16 percent DV
- Vitamin B6: 9 percent DV
- Pantothenic acid: 12 percent DV
- Thiamine: 6 percent DV
- Folate: 2 percent DV
The Linus Pauling Institute notes that getting sufficient amounts of vitamin B12 is linked to a lower risk for heart disease and cancer. Your body uses vitamin B12 for many functions, including making DNA, nerve and brain function and blood cell formation.
Vitamin B12 deficiency affects between 1.5 and 15 percent of people, especially among those who don't eat meat. A deficiency in vitamin B12 can cause symptoms including chronic fatigue, loss of appetite, constipation, nerve damage, impaired mental function and anemia, per the National Institutes of Health (NIH).
Vitamin B12 is also important during pregnancy. A deficiency in women may cause problems in babies, including impaired movement and delays in typical developmental milestones, warns the NIH.
If you live in an area that doesn't get much sunshine or you spend most of your time indoors, eating sardines may help prevent a vitamin D deficiency. Sardines are one of the few foods that offer such a high amount — 22 percent of your DV for vitamin D per can.
You need vitamin D for your muscles to move, for cellular communication and to help your immune system function properly. Along with calcium in sardines, vitamin D helps protect you from osteoporosis and bone disorders, per the NIH.
In addition, vitamin D may have a connection with medical conditions such as diabetes, hypertension, multiple sclerosis and autoimmune diseases.
2. They Contain Important Minerals
These little fish are also filled with minerals. Each can of sardines provides a good source of four minerals essential for improving and maintaining bone density:
- Phosphorus: 36 percent of your DV
- Potassium: 8 percent of your DV
- Magnesium: 9 percent of your DV
- Calcium: 27 percent of your DV
Getting too little potassium can deplete calcium in your bones, according to the NIH.
About 50 to 60 percent of magnesium in your body resides in your bones. Magnesium can increase bone density and may reduce the risk of osteoporosis in women after menopause, per the NIH. Other nutrients found in sardines that benefit your bones are copper, iron, zinc and vitamin D, according to American Bone Health.
One can of sardines in oil provides 88 percent of your DV for selenium, a trace mineral that helps regulate metabolism and is important for DNA production and thyroid gland function.
3. They're An Excellent Source of Omega-3 Fats
Fish is best known for its health benefits from its fatty acid content. All types of sardines are oily fish and an excellent source of polyunsaturated omega-3 fatty acids. Per can, sardines packed in oil contain 64 percent of your DV of omega-3 fatty acids.
Of the omega-3 fatty acids in sardines, there are two dominant types: EPA, vital for the health of your heart, inflammatory and immune system; and DHA, required for the development of your brain, eyes and nervous system.
Omega-3s are a vital nutrient that's linked to lower inflammation, risk of dying from heart disease, blood pressure, triglycerides, irregular heartbeats and atherosclerotic plaque, according to the Mayo Clinic.
Results of three large cohorts in 2017, published by the American Heart Association's publication Stroke, found the group that was administered omega DHA had a reduction in the overall risk of stroke after an 8 to 11-year follow-up. Stroke is a main cause of long-term disability and death in the U.S. Stroke can result from atherosclerosis, which could limit the flow of oxygen-rich blood to your heart and brain.
4. Sardines' Mercury Content Is Low
Mercury is a heavy metal found in the form of methyl mercury in fish in varying amounts. The mercury originates from many sources, including the natural environment such as volcanic activity, or from pollutants from industrial activities. Large predator fish that are at the top of the food chain typically contain the highest levels of mercury accumulation.
Sardines are one of the best fish choices lowest in methyl mercury content, per the FDA. The reason is that sardines are small and only eat plankton and not mercury-contaminated fish. They are short-lived, so mercury does not have time to build up in their flesh.
The FDA recommends a weekly intake of two to three servings of sardines, or 8 to 12 ounces for adults and 4 to 6 ounces for children age 4 to 7.
Eating Sardines During Pregnancy
The FDA recognizes the health benefits of eating fish, especially for pregnant people and young children. Pregnant people can eat up to 12 ounces per week.
Canned Sardines' Health Risks
The downside of eating sardines is their high cholesterol content — one can has 44 percent of your DV for cholesterol.
Although the Dietary Guidelines does not list a quantitative limit, it recommends people eat as little dietary cholesterol as possible.
So is it bad to eat sardines every day? It's best to stick to eating sardines about twice a week rather than every day. The American Heart Association warns that high cholesterol is a risk factor for heart disease, heart attack and stroke.
BPA in Cans
Another potential health risk of eating sardines may not come from the fish itself, but the can it's in. Cans can contain a toxic chemical, bisphenol A, known as BPA.
Despite concerns about its link to obesity, diabetes, heart disease and cancer, BPA is still used in food cans in America. Toxins in can linings can migrate to the food inside.
In a 2017 Center for Environmental Health study of canned foods, 38 percent of cans tested used BPA, and another 19 percent contained toxic PVC in the linings. Lab studies found BPA exposure may cause reproductive disorders, genetic damage and possibly increase the risk of breast cancer.
The Healthiest Sardines
Both fresh and canned sardines provide similar nutritional benefits. Sardines can be grilled, pickled, salted or smoked, but fresh sardines are very perishable so most sardines are sold as canned for longer storage.
Sardines packed in water or olive oil are a healthier choice than those in soybean oil or other types of refined oils. Sardines in tomato or mustard sauce are also healthy options, but could be higher in sodium.
- American Heart Association: "Stroke:" Fish and Omega-3 Fatty Acids
- Dietary Guidelines for Americans, 2015-2020: Chapter 1. About Seafood
- U.S. Food and Drug Administration: Eating Fish: What Pregnant Women and Parents Should Know
- American Pregnancy Association: Omega-3 Fish Oil And Pregnancy
- Mayo Clinic: Omega-3 in Fish: How Eating Fish Helps Your Heart
- American Heart Association: Omega-3 Fatty Acids and Incident Ischemic Stroke and Its Atherothrombotic and Cardioembolic Subtypes in 3 US Cohorts
- National Institutes of Health: Vitamin B12
- American Bone Health: Minerals for Bone Health
- National Institutes of Health: Potassium
- National Institutes of Health: Magnesium
- British Journal of Nutrition: Riboflavin (Vitamin B₂) and Oxidative Stress: A Review.
- National Institutes of Health: Vitamin D
- American Heart Association: New Guidelines: Cholesterol Should Be On Everyone's Radar, Beginning Early in Life
- USDA: "Canned Sardines"
- Center for Environmental Health: "Statewide Testing Finds More Than 90% of Canned Foods From Ethnic Groceries Contain the Toxic Chemical BPA"