As a variety of algae, often sold in powder form or in capsules as a food or dietary supplement, spirulina has a place in most health-conscious diets. It's linked to a range of potential health benefits, including a lower risk of oral cancer and enhanced immune function. The research supporting spirulina's health benefits has not yet caught up with its disease-fighting reputation -- more research is needed to learn how well it works, cautions the University of Maryland Medical Center -- but it does benefit your health because of its nutritional value. Make sure you consult your doctor before taking spirulina to avoid potential side effects.
Spirulina has 51 Calories and 0.85 g of Protein per 100 gram serving according to the nutrition facts provided by the USDA Food Composition Database.
Calorie and Macronutrient Breakdown
Supplement your diet with spirulina, and you'll modestly boost your calorie intake -- each 1/4-cup serving contains 81 calories. Approximately 79 percent of those calories come from its 16 grams of protein -- a nutrient required for tissue repair, immune function and hormone production. Eating a quarter-cup of spirulina also increases your carbohydrate intake by 7 grams, with 1 gram coming from dietary fiber. Spirulina is naturally low in fat -- each serving provides just 2.2 grams.
Use spirulina as a source of beneficial minerals. It comes loaded with iron and manganese -- each serving contains 532 micrograms of manganese and 8 milligrams of iron. This makes up 100 percent of the recommended daily iron and 23 percent of the daily manganese intake for men, and 44 percent of the daily iron and 30 percent of the daily manganese needs for women. Iron helps monitor your body's oxygen levels to prevent oxygen deprivation and also transports oxygen to your tissues. The manganese in spirulina helps you make proteins that your body needs for wound healing, and manganese's antioxidant function prevents tissue damage.
Spirulina's nutritional profile also includes ample amounts of thiamin and riboflavin, also called vitamins B-1 and B-2. Both of these vitamins play key roles in your cellular metabolism, which means they help you generate useable energy. Riboflavin also helps your liver metabolize toxins, while thiamin aids in producing new DNA. A 1/4-cup portion of spirulina provides 1.03 milligrams of riboflavin and 666 micrograms of thiamin. This makes up 94 percent of the recommended daily riboflavin and 61 percent of the daily thiamin intakes for women and 79 percent and 56 percent of the daily recommended riboflavin and thiamin intakes for men, respectively.
Considerations and Precautions
Spirulina likely makes a relatively safe addition to your diet, notes the University of Maryland Medical Center, but it has some potential drawbacks. Low-quality spirulina supplements might come contaminated with environmental toxins, which might pose a health risk. Spirulina's nutrient content might also interact with an underlying condition -- it's not safe if you have phenylketonuria and might aggravate autoimmune disorders, according to the University of Maryland Medical Center. Spirulina also contains a moderate amount of sodium -- 293 milligrams per serving, which is 13 percent of the maximum daily limit. This makes it more difficult to fit into sodium-controlled diets. Talk to your doctor before you start taking spirulina, and make sure you pick a high-quality variety to avoid exposure to environmental toxins.