Asparagus characteristics

• Rich in fibre
• An excellent source of vitamins B9 and K
• Aids kidney drainage and elimination
• Contributes to digestive health

Nutritional and calorific value of asparagus

Cooked asparagus, drained, 6 whole stalks /90 g:

• Calories: 20
• Protein: 2.2 g
• Carbohydrates: 3,7 g
• Lipids: 0.2 g
• Fibre: 1.8 g
• Glycemic load: Data not available
• Antioxidant power: Very high for raw asparagus. High for cooked asparagus.

Asparagus, whether green, white or purple, is a true concentrate of vitamins and minerals essential for good health. These nutrients, which are present in large quantities in the flesh of asparagus, include:

• Vitamin B9 (folate)
• Vitamin K
• Copper
• Iron
• Vitamin A
• Vitamin B1 (thiamine)
• Vitamin B2 (riboflavin)
• Vitamin B3 (niacin)
• Vitamin B6 (pyridoxine)
• Vitamin C
• Vitamin E
• Manganese
• Phosphorus
• Selenium
• Zinc

The benefits of asparagus

Very few studies have evaluated the specific human health benefits of asparagus. However, several prospective and epidemiological studies have shown that a high intake of fruit and vegetables reduces the risk of cardiovascular disease, certain types of cancer and other chronic diseases. The presence of antioxidant compounds in fruits and vegetables may play a role in this protection.

Rich in phenolic compounds

• Asparagus contains several phenolic compounds, the most important of which are flavonoids (mainly rutin) and phenolic acids (including hydroxycinnamic acid). These compounds are thought to have antioxidant properties, meaning that they reduce the damage caused by free radicals in the body.

Antioxidant carotenoids

• Asparagus contains carotenoid pigments, mainly beta-carotene, lutein, zeaxanthin and capsanthin. As asparagus ripens, the levels of lutein and beta-carotene tend to decrease, while the levels of zeaxanthin and capsanthin increase. Carotenoids are compounds with antioxidant properties, and eating foods rich in carotenoids is associated with a lower risk of certain cancers and cardiovascular disease.

An excellent source of folate (vitamin B9)

• Asparagus is rich in folate, making it the 5th richest food in folate after beef liver and certain legumes. Five cooked asparagus spears provide about 25% of the daily folate requirement for the general population and 15-20% for pregnant or breastfeeding women. Canned asparagus contains almost as much folate as fresh asparagus.

Fructooligosaccharides and prebiotic effect

• Fructo-oligosaccharides (FOS) or oligofructoses are a type of carbohydrate found naturally in certain vegetables and fruits such as asparagus, onions, chicory, artichokes, garlic and bananas. Fructo-oligosaccharides are recognised for their health benefits, including their prebiotic effect, their beneficial effect on mineral absorption and their ability to reduce blood cholesterol, triacylglycerol and phospholipid levels.

Sulphur compounds

How to choose the right asparagus?

Contrary to popular belief, thin asparagus is less tender than large asparagus because it is proportionally richer in woody fibres. Choose asparagus with tips that are tightly closed and compact. Purple asparagus can be found on the market. However, they lose their colour when cooked.

Storage

The longer asparagus is stored before being eaten, the more fibrous it becomes, especially at room temperature. Its sugars are quickly converted into starch and the formation of woody tissue is accelerated.

Refrigerator: first wrap the bottom of the spears in damp paper and put them in a plastic bag. Or place them upright in a glass with 5 cm of water. They will keep for 1 or 2 weeks.

Freezer: Once blanched in boiling water for 3 minutes, asparagus will keep for about 8 months. Cook them without defrosting.

Contraindications and allergies

As with all foods, there are some contraindications to eating asparagus. The most important of these contraindications is taking anticoagulants, which can be interfered with by the high levels of vitamin K in asparagus.

Vitamin K and anticoagulants

Asparagus is a good source of vitamin K. This vitamin, which is important for blood clotting, can be produced by the body and is also found in certain foods. People taking anticoagulants (Coumadin®, Warfilone®, Sintrom®, etc.) should eat a diet with a relatively stable daily vitamin K content. Asparagus is on a list of foods that should not be eaten more than once a day. The recommended dose is 250ml (1 cup) at a time. 

Asparagus and botulism

Foodborne botulism is caused by eating food contaminated with botulinum toxin. Improper home canning of low-acid foods, such as asparagus, has been implicated in several reported cases of foodborne botulism.

The symptoms of such poisoning appear within 6 to 36 hours of eating the offending food. They include double or blurred vision, difficulty speaking and swallowing, dry mouth and tiredness. Foodborne botulism is still rare, but because it can be fatal, special precautions should be taken to avoid it, especially when canning at home.