Creatine supports muscle energy and strength by producing energy in your body. It naturally occurs in foods like seafood, meat, and poultry.

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Creatine: 1.25 grams per 4-ounce serving

Herring contains up to 5 grams of creatine per pound, or 1.25 grams per 4 ounces raw, which makes it one of the richest sources of creatine.

Just 100 grams (a little over 3 ounces) of kippered herring has nearly 25 grams of protein and contains 11% and 9.5% of the Daily Value (DV) for magnesium and potassium.

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Creatine: 0.5 grams per 4-ounce serving

Salmon contains up to 0.5 grams of creatine per 4-ounce serving (2.0 grams per 1 pound raw).

Salmon is a rich source of omega-3s, polyunsaturated fatty acids that support brain and heart health.

It also contains nutrients like calcium, potassium, and vitamins A and B12.

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Creatine: 0.23 grams per 4-ounce serving

American plaice is a type of flounder. Plaice is in the same family as flounder, sole, and halibut.

Plaice contains 0.9 grams per pound (0.23 grams per 4-ounce serving). It is considered a lean fish because it has less than 4 grams of fat per 100 grams.

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Creatine: 0.45 grams per 4-ounce serving

Like salmon, bluefin tuna is a cold-water fish with higher fat and omega-3 content than leaner fish. It contains 1.8 grams of creatine per pound, or nearly 0.45 grams per 4-ounce serving.

Bluefin tuna is one of the few food sources of vitamin D, with 5.7 micrograms per 3.5 ounces (100 grams), or 28% of the DV. The same serving contains 36.5 micrograms of selenium, or 66% of the DV.

It is also a source of heart-healthy B vitamins.

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Creatine: 0.35 grams per 4-ounce serving

Cod contains 1.4 grams of creatine per pound, or 0.35 grams per 4-ounce serving. The same serving also provides 20 grams of filling protein and nutrients like calcium, magnesium, and vitamin D, which strengthen your bones.

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Creatine: 0.57 grams per 4-ounce serving

Pork contains 2.3 grams of creatine per pound raw, providing 0.57 grams per 4-ounce serving.

Pork also provides high-quality protein, B-complex vitamins, and essential minerals like iron and zinc.

Pork loin, the leanest cut of pork, contains moderate levels of saturated fat compared to beef. It also has a balanced fatty acid profile, with nearly equal amounts of monounsaturated and saturated fatty acids.

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Creatine: 0.41 grams per 3-ounce serving

Lean cuts of beef contain 2 grams of creatine per pound (about 0.41 per 3-ounce serving).

Lean beef is a high-quality protein offering essential nutrients like iron, zinc, and B vitamins, which support energy and overall health.

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Creatine: 0.41 grams per 3.5-ounce (100-gram) serving

Skinless, boneless chicken contains 0.36–0.39 grams of creatine per 100 grams (about 3.5 ounces). The same serving also provides 22.5 grams of protein.

Choosing skinless chicken will reduce the saturated fat you eat.

Creatine supplements may improve muscle strength. It may benefit athletic performance, particularly in rowing, soccer, and jumping.

Exercise may also maximize creatine’s potential. It may not matter if you take it just before or after working out.

Taking 4-5 grams of creatine daily for up to 18 months is generally safe. Up to 10 grams over 5 years may be safe. A short-term dose of 20 grams daily can be taken for 7 days, followed by 2.25-10 grams daily for 16 weeks.

Potential side effects of creatine include:

DehydrationCrampsStomach upset

Always consult a doctor before taking creatine supplements.

People who are pregnant or breastfeeding should not take creatine. Those with kidney disease, Parkinson’s disease, and bipolar disorder should also avoid creatine.