Let’s Talk Nutrition: Winter Squash

My grand-aunt loved to walk through her garden, pointing out the medicinal value of her fruits, veggies and herbs. One of her favorite dishes was homemade squash casserole. Thanks to her, squash is one of my favorite winter foods. Orange-gold cubes of roasted butternut squash with a touch of olive oil, acorn squash baked with a little cinnamon and maple syrup, or a fragrant and satisfying squash and sweet potato soup…But beyond the taste, I am amazed that such a simple food – so easy to store and prepare – provides such a range of nutrients. From skin care to cancer prevention, winter squash offers health in every bite.

Healthy skin: Squash contains carotenoids – orange pigments that accumulate in skin. They protect our skin from UV damage and rebuild layers, by promoting cell division to keep skin healthy. Low levels of carotenoids in skin have been associated with acne and dry skin, and aging skin. Eating a cup of squash provides about 400 mg of vitamin A as beta-carotene.

Sharp vision: Sunlight enters your pupils and streams to the back of the eye to a dish-like depression called the macula. The macula concentrates the two yellow-orange pigments essential for vision - lutein and zeaxanthin. The high concentration of these healthy pigments actually turns the macula into a yellow spot on the inner lining of your eye. These pigments enhance vision by blocking blue light. They also act as antioxidants repairing damage from UV light. Low levels of lutein and zeaxanthin cause macular degeneration, the leading cause of blindness in older adults.

Cancer prevention: Researchers are exploring the anti-cancer potential of yellow-orange vegetables like squash. Cucurbitacins, the cumbersome-sounding compounds first identified in squash, have a profound inhibitory effect on cancer in animal and cell studies when used as an extract. We don’t yet have hard proof about specific types of cancer that could be prevented when these cucurbitacins are consumed in whole foods. On the other hand, there is a lot of research documenting increases in levels of beta-carotene, a pigment found to help prevent breast and other cancers, when yellow-orange-green foods are eaten.

Inflammation: In addition to cancer inhibition, cucurbitacins were found to inhibit the Cox-2 enzyme, a pro-inflammatory enzyme implicated in diseases ranging from arthritis to cancer. Squash also contains ALA, an omega-3 fatty acid that helps to reduce inflammation. Many winter squash varieties (especially butternut) have a high glycemic index. The sugar spike from eating high glycemic foods leads to a spike in insulin, which in turn promotes inflammation. If squash is consumed with other high fiber foods, the blood sugar elevation after a meal would be more gradual. The anti-inflammatory components in the squash may help to counter its high glycemic index. In the case of acorn squash, it is often served with cinnamon - which helps to lower blood sugar. There is wisdom in our taste buds!

Energy balance: B-vitamins help to release energy from the foods we eat. They are water soluble, meaning we can’t store them and need to replenish them daily in our diet. Squash contains vitamin B1, B3, B6, folate and pantothenic acid. Inositol is a B-vitamin, which is also found in whole grains and other foods, associated with calming.

There is wisdom in eating for the seasons. Though my grand-aunt may not have known about curcubitacins, she didn't need to. Her delicious squash casserole ensured I'd get plenty of them. We can trust the earth to provide what's good for us. Winter squash is one of the best foods we can enjoy for good health.