Kale is an extremely nutritious food and arguably the healthiest vegetable found in a grocery store. However, it’s also an all-conquering health fad that since 2010 has swept through the natural health circles of the West Coast.
In two years, mentions of kale on American restaurant menus shot up by 233%. Kale is so popular that the quantity grown by American farmers increased by 57% from 2007 to 2012. There are US activists plotting to make October 2nd national kale day. Vermont plans to honour kale with the title of state vegetable, and Whole Foods reportedly sells 22,000 bunches of kale in its grocery stores across the US every single day.
The list of kale related foods is enormous. Kale chips, dried kale seasoned with spices, is available in many grocery stores. Green kale ice cream is a hit among vegans and even kale nail polish is available.
Other kale foods include kale baked eggs, pickled kale, raw kale noodles, apple kale muffins, candy kale chips (featuring honey, sea salt, and olive oil), kale cocktail (featuring gin, kale syrup, lime juice, orange, and Italian cynar), frozen kale cubes for drinks, kale pizza dough, kale brownies, kale sauce, cheesy kale crackers, kale fudge pops, kale cookies, kale vegan spice cake, avocado kale ice cream, kale cupcakes, and kale butter.
There’s even kale soda; a marketing genius must have worked out that by simply slapping the word kale on a soda can, consumers might be fooled into believing it was healthy. The actor Jake Gyllenhaal once need to lose 30 pounds for the movie Nightcrawler; his solution was running 15 miles a day and a diet of nothing but kale and bubble-gum. All this hype culminated with the creation of the kale-only diet (not a diet you should ever follow).
Thanks to all this, kale is now a dirty word among people who hate hippies and distrust passing fads and trends. However, cut through the hype and the old truth remains: the nutrition in kale is extremely powerful…
…and more important it’s very powerful for clearing up acne. Kale is even better for your acne and skin than the likes of broccoli.
Kale is extremely rich in acne nutrients
In the 1930s, prior to the beginning of World War 2, roughly 75% of Britain’s entire food supply was shipped in via cargo ships. This became totally unsustainable once the war began. After failing miserably to invade England during the battle of Britain in 1940, Adolf Hitler instead decided to force Britain to its knees through starvation.
Hence, his U-boat army massively stepped up the torpedoing of British cargo ships and by 1941, annual food imports had halved to 14.65 million tonnes. Something had to be done otherwise Britain would indeed starve to death.
The saviour of Britain was kale. The government launched the dig for victory campaign with the tagline of “spades not ships”. Citizens were encouraged to turn gardens, public parks and allotments into gardens, to grow as many potatoes, carrots and other cheap but nutritious vegetables as possible.
Kale was one of the most heavily promoted vegetables. Firstly, kale is a weed, which means that it grows extremely easily. It is extremely hardy since it is much less domesticated (and hence reliant on farmers) than the likes of broccoli and lettuce. Kale survives far longer into winter than other vegetables…
…but the biggest advantage of kale was its extraordinary profile of basic nutrients. Kale is far more nutritious than even broccoli, spinach, or cabbage. That nutritional profile can help you and your acne today. 100 grams of raw kale contains…
15376IU of vitamin A (308% of the RDA) – vitamin A is an all-important nutrient for acne patients because it directly controls the activity of your sebaceous glands, the glands that pump out oil (sebum) onto the surface of your skin. More vitamin A equals less oily skin, less blocked pores and less acne. Vitamin A also restrains the production of keratin, the protein that can glue dead skin cells together into pore blocking clumps.
Vitamin A can even defend against acne caused UV radiation in sunlight. The vitamin A in kale was a prime bonus in wartime Britain since it helps with eyesight; the night time blackout made good eyesight a top priority after citizens routinely fell into ditches and ponds during the early months.
120mg of vitamin C (200%) – vitamin C is a cofactor needed to create collagen, the main structural protein of the skin. More collagen equals greater skin hydration and faster wound healing (and thus healing of old acne). Vitamin C also lowers stress hormones behind acne and is the main water soluble antioxidant in humans.
34mg of magnesium (8%) – deficiency in magnesium is rampant, making kale all the more useful for acne. Magnesium is used for controlling acne-causing stress hormones, regulating the neurotransmitters necessary for sleeping well, and for lowering levels of insulin, the hormone which can cause oily skin and acne.
An ORAC score of 1770 – the ORAC scale measures antioxidants and kale clearly has plenty for acne. Kale reportedly has over 45 different flavonoid antioxidants, as well as the carotenoids lutein and zeaxanthin (coming up later). It scores higher than broccoli with its ORAC of 1510.
The strength of that acne nutrition alone makes kale one of the best vegetables an acne patient could eat. Broccoli is already a very healthy vegetable for acne but kale thrashes it.
The same weight of broccoli has 12% of the RDA for vitamin A, 156% for vitamin C, and 5% for magnesium. Kale’s vitamin A content (in the form of beta-carotene) is where it really shines for acne.
For the same acne nutrients, spinach contains 187%, 46%, and 17%. Cabbage contains 1%, 60%, and 3%. Brussel sprouts contain 15%, 141%, and 5%. Kale ranks first for vegetable acne-clearing nutrition.
Kale is also a fantastic source of calcium, with 14% per 100 grams. Calcium is not an especially useful mineral for acne, but as we discussed in my eBook Annihilate Your Acne, many acne patients have genetic sensitivities to the proteins and hormones found in milk. Dairy such as milk, cheese and yoghurt is the main source of calcium for most people, so many acne patients could use alternative source such as kale.
Gram for gram, kale contains more calcium than milk. Furthermore, a study on calcium from 1990 comparing milk and kale in human subjects found that the calcium in kale was 25% better absorbed than that of milk. The problem with milk is that the calcium is bound in a molecular complex with a protein called casein. Monogastric mammals like us have trouble digesting casein; while some manage well, many have a genetic inability to break down and extract the calcium in it.
Kale is also a highly alkalising vegetable and by reducing the overall acid load of the body, can improve calcium supplies by decreasing the requirement for acid neutralising minerals. Calcium is one of those minerals. Furthermore, so are acne minerals like magnesium, and potassium.
If you need an alternative calcium source that doesn’t cause acne, kale is one of the best available. Kale also contains small amounts of zinc (3% per 100 grams), a good amount of potassium, (14%), and 1021% of the RDA for vitamin K1.
Kale – the greatest source of lutein
Lutein is a member of the carotenoid class of antioxidants, a class with over 600 members that provide yellow, orange, and red pigments to foods (pumpkins, sweet potatoes, carrots). It is a phytonutrient, compared to zinc or vitamin C, which are micronutrients. Lutein is found in small quantities in multivitamins, since it is critical for eye health…
…but it’s also a stellar antioxidant for acne, and the good news is that kale is the single best source of lutein available from a grocery store. 100 grams of raw kale contains 35571mcg of lutein/zeaxanthin, and the next best food is spinach with 15691mcg when perfectly cooked. Eggs are well-known for their lutein content, but one whole raw egg contains just 331mcg. Only a rare flower called nasturtium contains more lutein than kale.
Lutein has many benefits for acne, but its best feature is being a fat-soluble antioxidant. If you’ve read the rest of this website, you’ll know the massive importance of antioxidants for clearing acne. Put simply, without antioxidants for acne the sebum (oil) on your face will be attacked by free radicals and produce a by-product called squalene peroxide, a by-product which blocks skin pores and leads to the inflammation behind acne itself. Lutein is especially potent for acne because squalene peroxide is a lipid peroxide, which only fat soluble antioxidants like lutein can destroy.
Many studies have shown the benefits of lutein for lowering lipid peroxide levels, and thus acne:
- This study examined both lutein and zeaxanthin and found that both of them prevented lipid peroxidation caused by free radicals. They both protected against UV damage from sunlight to the skin.
- This recent double-blind, placebo controlled trial fed 117 patients 10mg or 20mg of lutein for 12 weeks. Blood lutein levels significantly increased after 12 weeks. There was a large drop in malondialdehyde, which is the most commonly used biomarker of lipid peroxides. Inflammation levels fell after 12 weeks too, as measured by c-reactive protein. The scientists concluded that “the results support the possibility that lutein supplementation reduce biomarkers of CVD risk via decreased lipid peroxidation”.
- We also have this study on kale itself. Rats were fed a diet containing no kale, raw kale, or cooked kale. After 21 days, the rats fed kale had substantially lower malondialdehyde and lipid peroxidation products, two key signs of lipid peroxidation activity. The scientists concluded: “diet with kale, both raw and cooked, efficiently inhibited the lipid peroxidation process in rats’ organisms.”
It gets better for us acne patients too. While all the fat soluble carotenoid antioxidants in kale will prevent blocked pores and acne to some extent, lutein preferentially builds itself into the cells of your face. This scientific review analysed many animal and human studies and found that lutein is especially strong at protecting skin cells against light induced oxidative damage.
If you eat kale and hence eat more lutein, you are basically building a strong antioxidant armour against free radical damage and acne directly into your skin.
Aside from acne, lutein and hence kale are also terrific at protecting eye cells from damage as the eyes are another area where lutein tends to accumulate. Lutein accumulates in high concentrations in the macular, the centre of the eye’s retina, where it is an efficient absorber of blue light. Hence, lutein can protect against light-induced damage, which is believed to play a role in the development of age-related macular degeneration (AMD).
There’s also this study which found that Alzheimer’s patients have lower levels of lutein in their red blood cells. Lutein isn’t the only useful phytonutrient for acne in kale; it contains many sulphurous compounds which, when digested, generate healthy by-products such allyl-isothiocyanate, phenethyl-isothiocyanate, and benzyl-isothiocyanate, which are all linked to cancer prevention.
This study found that regular supplementation with kale juice could increase levels of gluthathione, an indigenous antioxidant which many acne patients are deficient in. The sulphurous compounds are likely responsible; the human body requires sulphur to manufacture glutathione. The study concluded that kale had a generally positive effect on antioxidant levels.
Kale is also a natural source of indole-3-carbinol, the compound from which the popular estrogen-reducing acne supplement DIM is derived. Like broccoli, kale is a good source of sulforaphane. As we discussed in this article, sulforaphane can lower inflammatory biomarkers linked to acne such as TNF-a. Chronic inflammation is the main cause of acne and acne patients generally have elevated levels of TNF-a in their skin samples.
The truth about goitrogens in kale
If you think that kale sounds like a perfect health-giving food then there’s a lot of people who want to tell you otherwise. There’s a whole subsection of nutritionists who fear kale and indeed any cruciferous vegetables.
You see, broccoli, kale, cabbage, brussel sprouts, bok choy, mustard greens, and so on contain compounds called goitrogens, which are said to block the uptake of iodine into the thyroid and hence block the production of vital thyroid hormones. It’s argued that those with thyroid problems should not even think of eating kale, and that in fact, their entire superfood status is a massive injustice.
The truth is that goitrogens do exist and at high intakes they can block iodine uptake into the thyroid altogether. Some animal studies have found that large doses of the goitrogens found in kale can negatively affect thyroid function…
…but the good news is that goitrogens can only cause harm and acne in certain circumstances, such as…
An iodine deficient diet – iodine deficiency is a global pandemic. Soils are depleted of iodine worldwide and many of us neglect seafood, the biggest source, in favour of industrially produced chicken and beef. The small iodine blocking effect of goitrogens is only problematic if you’re getting very little iodine anyway. Proper intakes of iodine provide a defence against goitrogens. You can get iodine from seaweed, eggs, strawberries, and seafood.
Massive quantities – apparently one woman ended up in a hypothyroid induced coma after feasting on kilograms of raw bok choy every single day. There’s no need to eat that many cruciferous vegetables either for your health or your skin.
Cooked raw – cooking is the easiest way to neuter the goitrogen problem of kale. Among cruciferous vegetables more generally, steaming reduces the goitrogen content by 30%, boiling by 65%, and boiling and discarding the water by a massive 90%.
The only real circumstance where you should minimise kale (though not eliminate entirely) is if you have existing thyroid problems. Still, there’s a good chance that you can solve those problems through iodine supplementation anyway, and then kale will be safe once more. Whether goitrogens cause acne has never been proven.
Pregnant women also require more optimal thyroid function to guarantee the health of the baby and hence are more sensitive to goitrogens. However, the quantities required for harm are still very high if you cook the kale properly. This study fed humans another cruciferous vegetable packed with goitrogens, raw broccoli sprouts, and noted no abnormal thyroid activity at the end.
So in other words, the goitrogens in kale are only a minor threat to health and acne and their danger can be averted with a small amount of planning.
What’s more, kale has numerous other health benefits that have nothing to do with acne. One especially interesting one is kale’s ability to lower levels of LDL, or the “bad” cholesterol. The mechanism through which it does so is very interesting. The human liver uses cholesterol as a building block to produce bile acids, specialized molecules that help to digest and absorb fat through a process called emulsification. When humans eat any meal containing fat, these bile acids get released into the intestine where they ready the fat for interaction with enzymes and absorption into the body.
Like all cruciferous vegetables, kale is rich in fiber. The certain types in kale are able to bind with the bile acids in the intestine and prevent them from interacting with fat molecules, causing the bile acids to remain in the intestine where they are eventually removed. Now that sounds like bad news at first, interrupting your body’s normal digestion of fats…
…but it winds up well for your cardiovascular health because it triggers your body to manufacture more bile acids to compensate. To achieve that your body must draw upon its store of cholesterol, thus lowering your blood levels and hence achieving through mere nutrition what millions of people seek to achieve through strong pharmaceutical drugs like Statins.
Studies have confirmed that kale lowers cholesterol. One study found that the cholesterol lowering power of kale was comparable to the prescription drug cholestyramine. Kale was found to bind up to 42% of the bile acids; only collard greens, which bound 46%, performed better.
In this 2008 study, scientists supplemented the diet of some hypercholesterolemic men with kale juice, and after 3 months, LDL cholesterol levels had fallen by 10%. Furthermore, levels of the “good” HDL cholesterol had risen by 27%.
Conclusion – possibly the best green vegetable for acne
The old saying “there’s no smoke without fire” applies well to kale; kale-mania was justified until the hippies took over.
While adopting an all kale diet is a waste of time for acne, adding a serving kale to your daily diet will feed your skin many of the strongest acne clearing nutrients like vitamin A and C, and will benefit your heart health too.
The final question is how to cook it, for optimal acne nutrition. Every cooking method will deplete the vitamin C count slightly, but studies show that steaming preserves the acne nutrition the best. I advise you to steam kale moderately to lower the goitrogen count, and also improve the taste, but skip boiling, because it can slash the vitamin C content by up to 70%. Also, one study found that the cholesterol-lowering ability of raw kale improved significantly when it is steamed.
Organic kale is superior for acne since kale consistently appears on the annual “dirty dozen” list of foods with the highest agrochemical residue. If organic kale is unaffordable or unavailable to you, then the sheer volume of acne nutrition in kale will still outweigh the pesticides and herbicides for a net benefit against your acne.
Finally, there are two main varieties of kale for an acne patient to consider: curly kale, the standard variety, and dinosaur kale.
Both are full of acne nutrition but dino kale is superior; the acne minerals in dino kale are more bioavailable due to dino kale containing less oxalates, acids which bind with minerals like magnesium and calcium. Dino kale is quite uncommon but keep your eyes open!
Thanks for reading!