Edible Food Parts You Never Knew You Could Eat

December 12, 2017

Across America, food “scraps” are often trimmings, skins and seeds tossed in the garbage. But as I started investigating these “waste products,” I quickly found many of these actually serve as edible food parts with robust nutrition. In fact, many ancient cultures, including Chinese medicine and Native American remedies, tapped the healthy compounds in some of the edible food parts below.

Beyond that, using every part of food we can also helps reduce food waste. In the United States, organic waste is the second highest component of landfills, which serve as mega methane emitters. And get this: 30 to 40 percent of the food we buy in this country is wasted. That’s 20-plus pounds of food per person per month. (1)

Learning more about edible food parts not only enhances your nutrition, but also helps solve a waste problem, too. A true win-win. Let’s dig in…

Edible Food Parts You Never Knew You Could Eat

1. Squash Scraps

Squash blossoms. Squash blossoms aren’t just for honeybees. In fact, scientists found that the spinasterol compound isolated from squash flowers harbored anticarcinogenic potential. The concentrated form of spinasterol applied to skin tumors in a mice study decreased the number of tumors by 65 percent. (2) You can eat the blossoms raw in salads, but they are notoriously delicious fried. For a healthier version, coat in egg whites, almond flour and lightly fry in avocado oil.

While you may be hard-pressed to find the edible flower of squash in the grocery store, you can often score them at the farmer’s market or in your own garden.

Squash skins. Ever peel a squash? Chances are, you were thanking your lucky stars if you didn’t knick a finger or worse. The great news? Unless you’re dealing with rough spaghetti squash skin or waxed squash skin, you can leave it on. (I always recommend choosing organic to avoid pesticide residues.)

The interesting backstory on squash skin nutrition: Portuguese scientists published a study in 2015 aiming to figure out if the edible food parts of squash had any value. In essence, they were trying to figure out if this waste byproduct of the food industry could be utilized for other healthy purposes. Turns out, the skin is raging with powerful antioxidants that mop up harmful free radicals. Perhaps the best part? The oven-dried samples showed higher phenolics and antioxidant activity values, perhaps due to increased bioactivity after roasting it in the oven. The authors concluded: (3)

“This work shows that the residues produced from agro-food industries, like pumpkin shells and seeds are potentially good sources of antioxidant compounds like polyphenols, beneficial for human health.”

No more skinning squash means my kitchen will be a much safer place during squash season.

2. Kiwi Skins

Growing up, my favorite way to enjoy kiwi nutrition consisted of cutting the fruit in half and then scooping the green, juicy flesh out with a spoon. The skin was always trashed — or compost-bound until I learned about the health benefits of kiwi skin.

Kiwifruit serves as a powerful prebiotic, serving as fuel for the beneficial organisms in your microbiome. (4) It also helps improve sleep quality. Eating two kiwis before bed can improve total sleep time and efficiency by up to 13 percent, thanks to medically useful compounds like antioxidants and serotonin. (5)

But what about the skin? The fuzzy texture of kiwi fruit is strange to some, but others liken it to the skin of a pear or a peach. The kiwi industry encourages people to eat the fruit’s skin, noting that the skin contains triples the amount of fiber as the fruit. Not peeling the skin also provides more vitamin C. (6) Always wash the skin and choose organic whenever you can.

3. Corn Silk

When you’re shucking corn on the cob, chances are you toss the silk. (Or even get annoyed by it when it sticks to the cob and stuck in between your teeth.) Turns out, there are some health benefits of this edible food part. I recommend sticking to food amounts and avoiding mega-doses, though.

Based on folk remedies, corn silk has been used as an oral antidiabetic agent in China for years, thanks to its potential impact on blood sugar levels. Corn silk contains proteins, vitamins, carbohydrates, calcium, potassium, magnesium, fixed and volatile oils, steroids such as sitosterol and stigmasterol, alkaloids, saponins, tannins and flavonoids. Over time, researchers also discovered corn silk harbors anti-fungal properties, too. Corn silk has also been used in many parts of the world for the treatment of edema, as well as for cystitis (a common cause of cloudy urine), gout, kidney stones and certain prostate problems. (7)

Some people actually chew on the mildly sweet, threadlike strands, but it’s common made into a tea, too. Known as a diuretic, some people drink corn silk in tea form to ease urinary tract infection symptoms. (8, 9) People with high blood pressure symptoms are known to turn to corn silk tea, too, thanks to its diuretic properties. (10) Because of that, it can decrease potassium levels in the blood, so be sure to consult with your doctor to make sure it’s the right fit for you and won’t interact with your medications. If you’re allergic to corn, it’s best to avoid this edible food scrap, too. (Hey, you can always compost it!)

While corn silk is relatively safe for many, here’s one more word of caution: Always look for organic corn products when consider edible food parts. Nonorganic versions are likely genetically modified with residues of glyphosate, the main ingredient in Monsanto’s Roundup. Glyphosate is toxic and an endocrine disruptor in human cell lines. (11)

4. Strawberry Stems

Strawberry nutrition usually focuses on the fruit’s robust manganese and vitamin content, but it turns out, the leaves are potent health powerhouses, too. In fact, the berry’s fresh leaves contained higher ORAC values than the actual fruit part. (12) Just a quick refresher: Antioxidants are evaluated by an ORAC Score (oxygen radical absorption capacity) and tests the power of a plant to absorb and eliminate free radicals.

In researching edible food parts, I stumbled upon several studies investigating the “value-added” potential of certain food parts. In other words, scientists are actively looking at scraps like strawberry leaves and the potential to turn into healthy products. But to keep things simple, I suggest just tossing the leaves into your blender for smoothies or sprinkling on top of salads. Here’s why…

As it turns out, strawberry leaves are teeming with bioactive compounds, including anti-inflammatory, disease-fighting flavonoids like quercetin and kaempferol. (13) Studies show us that kaempferol inhibits cancer cell growth and induces cancer cell death, all while appearing to preserve normal cell viability. (14)

In addition, scientists identified ellagitannins as one of the distinguishing compound classes in strawberry leaves. The functional food industry is very interested in ellagitannin compounds, thanks to their potential to improve vascular health and prevent degenerative disease. (15, 16)

5. Onion Skins

Tossing away onion skins is a major no-no in my household, and for many reasons. First, you can actually use the skins to add nutrition and flavor to your homemade bone broth recipes. I throw onion skins and even whole onions (with skins) into a pot and simmer bones to create the base of a nourishing tonic. After a long, slow simmer, I strain out the skins and onions and build the rest of my soup from there.

While most studies looking at onion skin nutrition focus on extract forms, you can still obtain some added nutrition when you use the skins, particularly in a broth. (Plus, skipping store-bought broths helps save money, packaging, and in the case of canned broths, BPA toxic effects. Onion skins used for broth creation also helps with a high blood pressure diet.

Quercetin and other compounds in onion skins possess blood sugar-lowering potential. In fact, onion skins may improve your gut health in a way that helps blunt the negative side effects associated with eating a high-carb meal. (17) Studies also suggest that onion skin compounds potentially help: (18)

lower blood pressure
lower inflammation
improve insulin resistance
thin the blood, reducing the risk of clots
lower cholesterol

6. Broccoli Leaves

If your favorite farmer’s market stand sells broccoli with most of the leaves stripped, they’re doing you a disservice. Turns out, broccoli nutrition isn’t limited to just the florets; the leaves are loaded with antioxidants ready to take on free radicals circulating in your body. These harmful free radicals are linked to cancer, accelerated aging and all sorts of health problems. In fact, broccoli leaves pack potent anticancer activity, according to a 2015 study published in Preventive Nutrition & Food Science. (19)

Try boiling the leaves for a few minutes to use as a wrap alternative or chop and sauté like other greens.

7. Cauliflower Leaves

Ever tap into romaine lettuce nutrition by grilling the greens? You can do the same type of thing with cauliflower leaves. Most people choose to only cook and consume the white “head” of cauliflower, since the tougher stem and leaves can cause digestive upset for some people and tend to be tougher in texture. But others can tolerate the greens. If that’s the case, I suggest trying out this roasted cauliflower leaf recipe.

8. Watermelon Rinds

When studying the potential toxicity of watermelon rinds, scientists were pleasantly surprised that it appeared safe to eat. In fact, a 2015 study published in Research Journal of Environmental Sciences, researchers tout eating watermelon rinds as a way to obtain nutrients while also reducing food waste. (20)

Researchers at Texas A&M University found the rind is loaded with citrulline, the precursor to the circulation-improving amino acid arginine. (21)

According to the study:

“The citrulline-arginine relationship helps heart health, the immune system and may prove to be very helpful for those who suffer from obesity and type 2 diabetes. Arginine boosts nitric oxide, which relaxes blood vessels, the same basic effect that Viagra has, to treat erectile dysfunction and maybe even prevent it.”

Popular ways to utilize this edible food part include pickling, candying, creating chutney, using in Indian curry or as a cucumber replacement for gazpacho. (22)

9. Corn Husks (Kind Of)

OK, so not exactly edible, but organic corn husks shouldn’t be tossed in the garbage, either. You can soak dried corn husks in hot water and then use as a wrap to encase food to be steamed or baked. The husk imparts a mild corn flavor into the food. Remove the husk after cooking and compost, don’t eat it. (22)

10. Lemon Peels

That citrus zing you get from using lemon rinds in your recipes is so much more than a tastebud delight. Science consistently shows that lemon rinds harbor anticancer effects. One study in particular suggests a certain citrus peel-based product could serve as a treatment for prostate cancer. (23)

A University of Arizona study found eating citrus peels could actually help protect you from squamous cell carcinoma of the skin. (24) As always, opt for organic citrus so you avoid toxic pesticides. To get started, try this simple lemon pepper green beans recipe featuring lemon rinds.

11. Past-Its-Prime Lettuce

If you’re a gardener, you know all about “bolted” lettuce. This marks the end of the lettuce plant’s life cycle, a time when the lettuce goes into blossoming mode and sends up a thick seed stalk. I often think bolted lettuce in the garden looks like a mini summer Christmas tree. When you see this lettuce change, act quickly. The leaves become bitter, but if you catch your bolted lettuce early, you can clip off the lighter-colored leaves to salvage a few more summer salads. (25)

And get this: Some types of lettuce are actually prized for not their leaves, but their stalks. Cracoviensis lettuce is popular in China, where people peel the stalk and eat it like asparagus. Try chopping the stalk and adding to soups and stir-fries. (26, 27)

12. Certain Flowers

Eating edible flowers is an ancient practice. And using edible petals serves more as plate beautification, too. Often times, it comes with a side of health benefits, too. In a 2012 study published in the journal Molecules, researchers found that Chrysanthemum and Viola (pansies) were among the most mineral-dense edible flowers they tested. In fact, the could be considered a high-potassium food, since potassium levels in these flowers was higher than what we find in many fruits and vegetables. (28) Edible flowers also possess healthy levels of vitamins A and C, riboflavins, niacin and minerals like calcium, phosphorous and iron. (29)

You can sprinkle edible flowers like nasturtium (slightly peppery), pansies, okra leaves or squash blossoms on salads for a beautiful presentation.

13. Every Part of a Dandelion

Dandelion tea is a detox favorite, but you can also use the leaves and flowers in salads and smoothies. The dried, ground dandelion root can even serve as a coffee substitute.

Dandelion greens serve as a lutein powerhouses. This carotenoid helps keep the eyes safe from oxidative stress and the high-energy photons of blue light and may help prevent macular degeneration symptoms. (30)

In herbal medicine, dandelion has been used to treat infections, bile and liver problems. It’s also a diuretic. If you’re on potassium-sparing diuretics, ingesting dandelion could put you at risk of unhealthy potassium levels in the blood. (Proper potassium levels are crucial for heart health.) (31)

Final Thoughts on Edible Food Parts

Food “scraps” sometimes serve as nutrient-dense edible food parts.
Many of these edible food parts have been eaten for centuries in Native American and Chinese cultures, for instance.
Organic corn silk, kiwi skin, strawberry stems and watermelon rinds are some of the more popular edible food parts.
It’s best to stick to food amounts and avoid mega-doses supplements based on edible food parts.
Always check with a medical professional to make sure supplements made from these edible food parts won’t interfere with existing medications. As always, if you are pregnant or nursing, it’s also best to check in with your medical professional.