Consume too much, and you may be in for unpleasant symptoms such as abdominal pain, low blood pressure, kidney stones, tremors or convulsions & vomiting...
Can Spinach Be Dangerous?
The simple fact of biology is, living things really don't like to be eaten. Just like a zebra has predators, so do plants. Zebra can run away to avoid being eaten, but what can a plant do when a bug or human show up?
While we are masters of locomotion, plants are fantastic chemists. Alright, follow me up on this, I'm talking about secondary metabolites, or `plant toxins`.
One of the perks of us humans being intelligent is what we have learned to avoid highly toxic plants and have developed methods for deactivating the toxins of others. Though in certain cases, some people can have problems with plant food toxins that don't affect the rest of the population. For example, my friend grew up in the heart of Texas yet didn't have any problems with photosensitizers in lime or celery. It's strange but there are cases and I don't recommend you to google them (Image Alert), but some people do have problems and even experience 2nd-degree burns from eating limes.
Photosensitizers, technically called `furanocoumarins` are toxins in plants that make animals sensitive to light. And virtually all plant foods we normally consume have some level of defense against plant-eaters. According to the 1990 study titled `Dietary Pesticides (99% all-natural), led by biochemist Brune Ames, 99% of the pesticides in the American diet are chemicals that plants produce to defend themselves. Only 52 natural pesticides have been tested in high-dose animal cancer tests, and about half, 27 are rodent carcinogens, of these 27 are shown to be present in many common foods. What is crazy the study has found more than 49 natural pesticides just in cabbage alone.
Now before it starts to sound like I'm saying shopping in the produce section is slowly killing you, let me point out that we are not rats and that hormesis has to be taken into account. Hormesis is essentially the concept of Good Stress, - that is, `the dose makes the poison` or `what harms me in the right way and not too much makes me stronger.
For example, just like you and me, broccoli really doesn't like to be chewed on. So, when broccoli is cut or chomped on, glucoraphanin in the broccoli is activated through an enzyme myrosinase to form an isothiocyanate, a toxin called sulforaphane. This molecule is designed to kill small living creatures munching on it, but for us, it can be good, it's mild stress that our bodies gear up for and the end result is we wind up stronger.
Another substance found in common plant food with low-level toxicity is oxalate - it is found in spinach, beets, soy, lime peel, orange peel, and several others. Since oxalate is usually more concentrated in the leaves of plants, spinach is particularly high in it. According to Hascheck & Rousseaux`s book of toxicological pathology, insoluble plant oxalates include calcium oxalate. When animals eat these plants the crystals are immediately irritating, causing mechanical damage to the oral cavity and gastrointestinal tract.
Obviously, the levels in the food we normally eat are way too low to cause any immediately apparent effects, but high levels of oxalate are no joke. In 1989, a 53-year-old diabetic, alcoholic man died just a few hours after having 6g worth of oxalate from sorrel soup - this is equivalent to about half a kilo of spinach. However, keep in mind this person was already severely metabolically impaired. About 2,5 kilos or 5.5 pounds of spinach has 50% of killing a healthy person. Some research shows it would take about 25 grams of oxalic acid to cause death in a 145-pound person, which would equate to about 7.3 pounds of spinach. I think we are safe.
A compound oxalic acid
A few years ago, an interesting myth about the dangers of reheating boiled spinach began to make the rounds. It doesn't make you as strong as your grandmother told you, because, according to Penn State food scientists, spinach that is stored for a long time loses some of its nutritional value, especially in the first few minutes of cooking.
Raw spinach contains loads of oxalic acid, which can hinder the absorption of certain nutrients such as iron and calcium and be highly toxic. To make matters more interesting, it can also block the body's ability to absorb iron or calcium.
A compound oxalic acid, which is naturally present in many vegetables as stated above, can hinder the absorption of calcium. Spinach is rich in calcium, but the good news is that it can be broken down in the body so that there is no nutrient loss from steamed or sautéed spinach. However, its high concentration of iron and other toxic compounds prevents the body from absorbing a large proportion of calcium.
It is difficult, if not impossible, to give an exact time frame, but it is clear that leafy vegetables such as spinach can pose a greater risk to food safety than meat. Like kale, spinach does not last long and can in some cases cause diarrhea, nausea, vomiting, and even death.
Spoiled spinach can cause problems for anyone who eats it, including health risks such as food poisoning. Spinach is otherwise a healthy vegetable, but if you are prone to kidney stones, you should reduce your spinach intake and forgo all its goodness. In general, healthy people are healthy, but some can cause serious health problems, such as kidney failure, heart disease, and even death.
If you have kidney stones or take certain medications such as blood thinners, you should avoid spinach. If you have kidney stones, avoid or drastically reduce the intake of spinach and other oxalate-containing foods for at least two weeks.
But some - mostly spinach, beet greens, and Swiss chard - are also high in oxalic acid, the compound that gives hearty greens their signature earthy, slightly bitter taste. Consume too much, and you may be in for unpleasant symptoms such as abdominal pain, low blood pressure, kidney stones, tremors or convulsions & vomiting.
But please don’t think that this means dark, leafy greens aren’t part of a healthy diet. In moderation, they’re perfectly fine, and in fact, they are very recommended consuming especially on a ketogenic diet.
Most of the carbs in spinach consist of fiber, which is incredibly healthy. Dark, leafy greens are literally a nutritional powerhouse, filled with essential nutrients including vitamins C and A, iron, and folate, also filled with calcium, an essential mineral for bone health. Spinach also may help with eye health, cancer prevention, blood pressure... Basically, spinach is an extremely rich-nutrient vegetable.