Although it is common practice here in Mexico to use the leaves raw in agua fresca, a tea-like cold drink, chaya does contain cyanogenic glycosides, which are a source of cyanide poisoning. Therefore according to most US and English resources it should not be eaten raw. Boiling leaves for at least 5 minutes releases the cyanide and makes the leaves safe to eat. Even though some people tend to eat raw chaya leaves, it is unwise to do so.
An analysis of raw and cooked samples of chaya leaves revealed that cooking may increase the relative composition of carbohydrate and fat and decrease relative composition of crude fiber and protein. On the other hand, cooked samples of chaya leaves were considerably higher in calcium, phosphorus and iron while the potassium content was relatively lower than in the raw samples. The increase in some of the mineral nutrients may be due to the cooking process, which allows extraction of the nutrients from the tissues, therefore increasing the percentage of mineral elements while decreasing moisture content (Booth, S., R. Bressani, and T. Johns. 1992. Nutrient content of selected indigenous leafy vegetable consumed by Kekchi people of Alta Verapaz, Guatamela. J. Food Compos. Anal. 5:25-34.).
Chaya must not be cooked in Aluminum, as a toxic reaction can result causing diarrhea. Chaya gets a little tougher when cooked, so use the more tender young leaves for cooking.
Some types of Chaya have stinging hairs on the stems and leaves. You need to be cautious if using these leaves and wear gloves or plastic bags over your hands until the stinging hairs are completey removed. Finding chaya leaves, and or plants to grow the chaya without the stinging hairs is fairly easy so avoid the spiny ones whenever possible.
From Purdue's Horticultural Studies area:
Nutritional composition of leaves of "chaya"
(Cnidoscolus chayamansa McVaughn) per 100 g fresh weight.
Water (%) 85.3
Protein (%) 5.7
Fat (%) 0.4
Crude fiber (%) 1.9
Total CHO (%) 4.2
Ash (%) 2.2
Calcium (mg/100g) 199.4
Phosphorus (mg/100g) 39.0
Potassium (mg/100g) 217.2
Iron (mg/100g) 11.4
Ascorbic acid (mg/100g) 164.7
Carotenoids (mg/100g) 0.085
Average nutritive valuey 14.94
Health claims attributed to the ingestion of chaya:
Improve blood circulation,
disinflame veins and hemorrhoids,
help lower cholesterol,
help reduce weight,
augment calcium in the bones,
decongest and disinfect the lungs,
prevent anemia by replacing iron in the blood,
improve memory and brain function and
combat arthritis and diabetes.
chaya is richer in iron than spinach, and a powerful source of potassium and calcium.
I am decreasing the vitamin and mineral supplements I take due to this new agua de chaya regime; I am still in the experimental phase, and after 3weeks don't yet feel ready to offer up an opinion on the benefits. Time will tell!
I came across this info on cyanide poisoning, which I find very interesting:
How can people be exposed to cyanides?
People may be exposed to low levels of cyanides in their daily lives from foods, smoking and other sources. Eating or drinking cyanide-containing foods may cause health effects. Breathing cyanide gas, especially in a poorly ventilated space, has the greatest potential for harm. Lethal exposures to cyanides result only from accidents or intentional acts. Because of their quick-acting nature, cyanides may be used as agents of terrorism.
How does cyanide act in the body?
After exposure, cyanide quickly enters the bloodstream. The body handles small amounts of cyanide differently than large amounts. In small doses, cyanide in the body can be changed into thiocyanate, which is less harmful and is excreted in urine. In the body, cyanide in small amounts can also combine with another chemical to form vitamin B12, which helps maintain healthy nerve and red blood cells. In large doses, the body’s ability to change cyanide into thiocyanate is overwhelmed. Large doses of cyanide prevent cells from using oxygen and eventually these cells die. The heart, respiratory system and central nervous system are most susceptible to cyanide poisoning.
What are the specific signs and symptoms of cyanide poisoning?
The health effects from high levels of cyanide exposure can begin in seconds to minutes. Some signs and symptoms of such exposures are:
- Weakness and confusion
- Nausea/feeling "sick to your stomach"
- Gasping for air and difficulty breathing
- Loss of consciousness/"passing out"
- Cardiac arrest
the chaya plant foto is from the internet, the other 2 are mine.
Also, much of this info came directly from internet searches,
although some words are actually mine.