The picture of Popeye the Sailor eating spinach and gaining strength to fight all opponents is not easy to forget for his fans. It brings forth smiles on many a face and highlights the nutritious value of a vegetable that at least children don’t want to eat.

This green leafy vegetable is a nutrient rich food and is said to have its origins in the Middle East — more precisely in Afghanistan and Turkistan — though some believe it to be a native of Persia (now Iran). Arab traders carried spinach to India and China and it’s now easily available all over the world.

Spinach has a high nutritional value and is extremely rich in antioxidants, especially when fresh, steamed or quickly boiled. It is a rich source of vitamins A, B, C, E and K, as well as magnesium, manganese, folate, iron, calcium, potassium, folic acid, protein, copper, zinc and omega 3 fatty acids.

Consumption of this healthy food is good for diet conscious people as it is low caloric yet abundant in nutrients, especially iron, vitamins and calcium. Spinach contains more than a dozen different flavonoids that function as anti-cancer or anti-inflammatory agents. Compared with other healthy vegetables such as broccoli, cabbage and Brussel sprouts, only spinach showed significant protection against the occurrence of aggressive prostate cancer.

Minerals found in spinach help to balance off the high acid diet that most of us consume and which is a cause of many health problems. Folate or folic acid lowers the levels of homocysteine, a non-protein amino acid that damages the arteries; in other words it protects against cardiovascular diseases. Carotenoids protects against eye diseases such as cataract and muscular degeneration. A cup of fresh spinach or 1/6 cup of cooked spinach contain twice the amount of our daily vitamin K needs; hence it contributes greatly to a healthy nervous system and brain function by playing an essential role in the synthesis of sphingolipids, the crucial fat that makes up the myelin sheath around our nerves. The high amount of vitamin A in spinach also promotes healthy skin by allowing for proper moisture retention in the epidermis, thus fighting psoriasis, keratinisation, acne and even wrinkles.

Spinach is not only easily available in the market, it can be grown in the kitchen garden at home. It can be eaten raw in salads or sandwiches, as it contains more nutrients than iceberg lettuce. It is also used in soups, pastas, lasagne and other dishes to improve taste and nutritive value. Sautéed spinach with garlic can also be served as a topping for baked potato with steak and roast. When cooking it should be lightly cooked to retain its nutritional value; also when boiling spinach care should be taken to use as little water as possible and boil for the shortest time possible.

But as all good things spinach too has its negatives. It contains goitrogens, a chemical substance which interferes with the functioning of the thyroid gland. Therefore, it is inadvisable for people with thyroid problems to eat spinach. Also, people who have a history of gout or rheumatoid arthritis should limit the amount of raw spinach they eat.

While oxalic acid in spinach cleans our intestinal tract, it binds with iron and calcium and inhibits their absorption in the body; cooking breaks down cell walls and allows our body to absorb more nutrients, though cooking also turns oxalic acid into crystals that could damage the kidneys. Therefore, eating raw spinach on a regular basis increases the risk of kidney stones. Though not all kidney stones are oxalate based, it is recommended that people with kidney stones should check with their doctor if they should eliminate spinach from their diet. Cooking spinach may not completely destroy all the oxalates but it will certainly inactivate around 5 to 15 per cent. If, however, raw spinach is combined with food items abundant in Vitamin C such as citrus slices, the combination improves the absorption of iron.

Spinach is sold loose, bunched, packaged fresh in bags, canned, or frozen. Fresh spinach loses much of its nutritional value with storage of more than a few days. While refrigeration slows this effect to about eight days, spinach will lose most of its folate and carotenoid content, so for longer storage, it is blanched and frozen, cooked and frozen, or canned. It can be stored in the freezer for up to eight months.