Marks Daily Apple
Serving up health and fitness insights (daily, of course) with a side of irreverence.
17 Apr

Smart Fuel: Spinach

Perhaps Popeye had it right. He pounded spinach for super-human strength and loved olive oil (although granted, it was a girl, not the healthy fat Rachel Ray is always harping on about!). But is spinach really good for your muscles and can it give you the boost you need to take on ol’ Bluto?

Let’s start with the most basic stuff: Calorie for calorie, spinach is perhaps one of the most nutrient dense vegetables out there (and it’s no slouch in the flavonoid department, but we’ll talk about that in a minute). In the vitamin department, it logs literally off-the-charts levels of vitamin K and vitamin A, providing 1110% and 234%, respectively, per 1 cup serving of boiled spinach (or 6 cups of raw spinach). Why would this be important? Well, vitamin K is important for bone health (especially when combined with calcium and magnesium, spinach’s other bone-building nutrients) and vitamin A is important for reducing the amount of free-radicals in the body as well as preventing cholesterol from oxidation – which is the process whereby cholesterol can cause damage to arteries. This effect is further amplified when the vitamin A is combined with vitamin C – which spinach also has in spades – a combination that is also thought to reduce inflammation, particularly among patients suffering from asthma, osteoarthritis and rheumatoid arthritis.

Rounding out the nutrient profile, spinach is an excellent source of folate, which is important for blood health, as well as magnesium, which mimics the role of angiotensin inhibitors to help regulate blood pressure and prevent heart disease. When cooked, spinach is also an excellent source of iron, which is one of the primary components in hemoglobin – and thus has a role in energy production and metabolism.

Now on to the flavonoids: Current research suggests that are 13 different flavonoid compounds in spinach that not only serve as antioxidants but may also reduce the risk of cancer. Specifically, there are several spinach extracts that have been shown to reduce the risk of skin cancer, with one study published in the American Journal of Clinical Nutrition suggesting that consuming spinach or other dark leafy green vegetables can reduce the risk of skin cancer recurring among those with a previous history by as much as 55%. A study published in Cancer Causes & Control, meanwhile, also found that spinach and other vibrantly-hued vegetables could also reduce the risk of stomach cancer (gastric adenocarcinoma). Still need proof? A second study published in Cancer Causes & Control has also suggested that it may also reduce ovarian cancer risk while a study published in the September 2004 edition of the Journal of Nutrition suggests that the neoxathin contained in spinach may also help reduce the risk of prostate cancer.

But what about the muscles? Well, the reality is, spinach probably isn’t going to give you super human strength (or gargantuan muscles ala Popeye), but when it conveys this many other health benefits, perhaps it makes sense to keep on eating it and plan on outliving – as opposed to straight pulverizing – Bluto.

Spiff 27 Flickr Photo (CC)

Further Reading:

More Smart Fuel

FitSugar: Frozen Spinach Does the Body Good

The Consumerist: Spinach Facilities are Unsafe, Disgusting and the FDA Doesn’t Care

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Imagine you’re George Clooney. Take a moment to admire your grooming and wit. Okay, now imagine someone walks up to you and asks, “What’s your name?” You say, “I’m George Clooney.” Or maybe you say, “I’m the Clooninator!” You don’t say “I’m George of George Clooney Sells Movies Blog” and you certainly don’t say, “I’m Clooney Weight Loss Plan”. So while spam is technically meat, it ain’t anywhere near Primal. Please nickname yourself something your friends would call you.

  1. I had a kidney stone before, and when I was doing research about it I read that spinach was something that could definitely cause kidney stones. I wasn’t eating spinach so it wasn’t the cause of mine, but just curious on Marks’s thoughts on this?

    Jerry wrote on April 17th, 2008
  2. My concern with spinich is the high iron content, for males it is not good to have high blood levels, from what i’ve read it acts as a catalist & can promote free radical production, for pre-menopausal women this is less of an issue

    JC wrote on April 17th, 2008
    • Donate blood if you are able!

      Erin wrote on July 16th, 2013
  3. The posting on spinach says, “When cooked spinach is an excellent source of iron.” Does it have to be cooked to be such a good source?

    CC wrote on April 17th, 2008
    • Unless we’re talking about cooking it in an iron skillet, which would indeed add iron to the food, cooking neither increases nor decreases iron content. (Cooking often destroys vitamins, and I believe maybe fiber as well, but minerals are chemical elements and aren’t destroyed without nuclear reactions. They don’t usually evaporate either.)

      I suspect what is meant here is that cooking spinach decreases its volume (it wilts a lot!), while preserving the same total amount of iron… therefore the iron is more concentrated. A serving of cooked spinach is probably a greater amount of spinach (and therefore iron) than raw because of the shrinkage that occurs during cooking. But I’m just guessing that’s what’s meant here.

      Sally wrote on November 5th, 2009
  4. How lovely to happen upon this article as I eat my lunch, which, coincidentally, includes a spinach salad! To add to the others concerns about spinach, I had heard that spinach can also contribute to gout, a very painful joint inflammation. Odd that a substance purported to have anti-inflammatory properties would contribute to an arthritis-like condition.

    I wonder if this and the other negative health issues are only a concern when spinach is consumed in excessive amounts, or perhaps in combination with some other, less healthy foods? I have heard that brown colas can also be a factor in kidney stone growth, and my husband, who had a kidney stone a while back, had been a regular Pepsi consumer over the years, but never really ate spinach. Passing one stone got him to give Pepsi up really quickly!

    I, however, have had no ill effects from my consumption of spinach (by no means excessive), and until I do, will continue to enjoy it, even more happily now, knowing how many vitamins it has!

    Amy wrote on April 17th, 2008
  5. I love spinach… a LOT. But, I know the issues with eating it too much. For example, in this post, you said that one cup can provide 1110% of our vitamin K… but Vitamin K is not water soluble. Having such extreme amounts of it for prolonged periods of time is toxic.

    Ladyevidence wrote on September 30th, 2008
  6. Spinach is my favorite green to add to my primal green smoothies. It is by far the mildleist tasting green but possibly the most nutritious? That is too amazing!

    Primal Toad wrote on July 27th, 2010
  7. What about the part about spinach including high levels of oxalate, , it appears to be a major downside. How do you counter this?

    wd wrote on October 30th, 2010
  8. Spinach is great, just look at Ivan Drago…

    “Then how do you explain his freakish strength?”

    “Like your Popeye, he ate his spinach every day.”

    I must break you.

    Matt wrote on January 16th, 2011

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