New research has identified one of the key cancer-fighting mechanisms for sulforaphane, and suggests that this much-studied phytochemical may be able to move beyond cancer prevention and toward therapeutic use for advanced prostate cancer.
Scientists said that pharmacologic doses in the form of supplements would be needed for actual therapies, beyond the amount of sulforaphane that would ordinarily be obtained from dietary sources such as broccoli. Research also needs to verify the safety of this compound when used at such high levels.
But a growing understanding of how sulforaphane functions and is able to selectively kill cancer cells indicate it may have value in treating metasticized cancer, and could work alongside existing approaches.
The new findings on the unique abilities of sulforaphane were recently published in the journal Oncogenesis, by researchers from Oregon State University and the Texas A&M Health Science Center. The work was supported by the National Institutes of Health.
“There’s significant evidence of the value of cruciferous vegetables in cancer prevention,” said Emily Ho, professor and director of the Moore Family Center for Whole Grain Foods, Nutrition and Preventive Health in the OSU College of Public Health and Human Sciences, and lead author on this research.
“However, this study is one of the first times we’ve shown how sulforaphane can affect a histone methylation and alter gene expression in metasticized prostate cancer cells,” said Ho, who is also a principal investigator in OSU’s Linus Pauling Institute. “It begins a process that can help to re-express tumor suppressors, leading to the selective death of cancer cells and slowing disease progression.”
The evidence now shows that sulforaphane should have therapeutic value against some forms of cancer, Ho said, including late-stage, metasticized disease. Its multiple impacts on metabolic processes might also make it a valuable adjunct to existing therapies, helping them to work better.
No clinical trials have yet been done to test the value of sulforaphane in cancer therapy, although a trial is under way using sulforaphane supplements in men with high risk for prostate cancer. Results from that may help demonstrate the safety of higher-dosage supplements and set the stage for therapeutic trials, Ho said.
Dozens of studies have examined the health value of cruciferous vegetables such as broccoli, cauliflower, and cabbages, and many of them ultimately focused on the role of sulforaphane, one compound found in these foods. Broccoli sprouts contain some of the highest dietary levels of the sulforaphane precursor.
The new study identified a particular enzyme in prostate cancer cells, SUV39H1, that is affected by exposure to sulforaphane. Aside from potential dietary approaches, the researchers said that this establishes SUV39H1 as a new therapeutic target, in general, for advanced cancer.
Prostate cancer is one of the most commonly diagnosed cancers in the United States, and existing therapies include surgical removal of the prostate, radiation therapy, hormones or other approaches. Although often slow growing, prostate cancer can be much more aggressive if it metasticizes to other areas of the body, at which point survival rates decrease dramatically. In the U.S. it’s the fifth leading cause of cancer death.
In laboratory studies, sulforaphane has shown toxicity to a number of human cancer cell lines, including prostate, breast, ovarian, colon and pancreatic cancer, and in animal studies it decreased metastases of prostate cancer.
A perfectly ripe, juicy tomato, still warm from the sun. Sweet carrots, pulled from the garden minutes (or even seconds!) before they’re eaten. Growing your own vegetables is one of those activities that balances practicality and indulgence. In addition to the convenience of having the fixings for a salad or light supper right outside your door (or on your windowsill), when you grow your own vegetables, you’re getting the most nutritional bang for your buck as well. Vegetables start losing nutrients as soon as they’re harvested, and quality diminishes as sugars are turned into starches. For the tastiest veggies with the best nutrition, try growing a few of these nutrient-dense foods in your own garden.
And don’t let the lack of a yard stop you – all of them can be grown in containers as well.
1. Broccoli
Broccoli is high in calcium, iron, and magnesium, as well as Vitamin A, B6, and C. In fact, one cup of raw broccoli florets provides 130% of your daily Vitamin C requirement.
Grow Broccoli in Containers: One broccoli plant per pot, pots should be 12 to 16 inches deep.
What to Watch Out For: Cabbage worm. If you start seeing pretty white butterflies fluttering around your broccoli, you’re guaranteed to start seeing little green worms all over your broccoli plants. To avoid this, cover your broccoli plants with floating row cover or lightweight bed sheets. If you start seeing cabbage worms, simply pick them off by hand.
2. Peas
There is nothing like peas grown right in your own garden – the tender sweetness of a snap pea just plucked from the vine is unlike anything you can buy in at a store. Aside from being absolutely delicious, peas are high in fiber, iron, magnesium, potassium, and Vitamin A, B6, and C.
Grow Peas in Containers: Sow peas approximately 2 inches apart in a pot that is at least 10 inches deep. Provide support for peas to climb up.
What to Watch Out For: Hot weather. Once the weather turns hot, pea production will pretty much shut down. Grow peas in early spring and late summer/autumn, or any time of year when temperatures are consistently between 40 and 85 degrees Fahrenheit.
3. Beans (especially navy beans, great northern beans, kidney beans)
While snap beans (green beans/wax beans) are a great addition to any garden, it’s the beans we grow as dried beans that are real nutritional powerhouses. Dry beans, in general, are high in iron, fiber, manganese, and phosphorous.
Grow Beans in Containers: Bush beans are your best option for growing in containers. Plant beans four inches apart in a container that is at least 12 inches deep.
What to Watch Out For: Harvest at the right time. Harvest dry beans when the pods have completely dried on the vine. The pods should be light brown, and you should be able to feel the hard beans inside. Shell the beans, and let them sit out a few days to ensure that they’re completely dry before storing them in jars in a cool, dark, dry place.
4. Brussels Sprouts
The bane of many a childhood, Brussels sprouts get a bad wrap mostly due to overcooking. When prepared right, Brussels sprouts are sweet, tender, and delicious. They also provide tons of fiber, magnesium, potassium, and riboflavin, as well as high levels of Vitamins A, B6, and C.
Grow Brussels Sprouts in Containers: Grow one plant per 16-inch deep container.
What to Watch Out For: Cabbage worms (see “Broccoli, above.)
5. Tomatoes
Fresh, homegrown tomatoes are the reason many gardeners get into vegetable gardening in the first place. There’s just nothing that compares to eating a perfectly ripe tomato, still warm from the sun. Tomatoes are also incredibly good for us, packing plenty of fiber, iron, magnesium, niacin, potassium, and Vitamin A, B6, and C. They’re also a great source of the antioxidant lycopene.
Grow Tomatoes in Containers: Container sizes will vary depending on the variety you’re growing. If you’re growing an indeterminate variety, your container will need to be at least 18 inches deep. For determinate varieties, 12 inches is a good depth, and for dwarf or “patio” type tomatoes, 8 inches is perfect. One tomato plant per pot.
What to Watch Out For: Tomato horn worm can be a problem in many areas – these large caterpillars should be removed by hand whenever you see them. Also watch out for signs of blight, which is a real problem in many parts of the U.S.
6. Red Bell Peppers
Red bell peppers are high in potassium, riboflavin, and Vitamins A, B6, and C – in fact, one cup of red bell pepper packs an amazing 317% of the recommended daily allowance of Vitamin C and 93% of the recommended Vitamin A.
Beets are a great “two-fer” crop – you can harvest the beet roots, of course, but you can also harvest and eat the greens. Young beet greens are delicious when added raw to a salad, and larger beet greens can be sauteed as a quick side dish or used the way you’d use other greens such as spinach. Beet roots are very high in iron, potassium, and vitamin C. Beet greens are even better, as they are high in iron, calcium, magnesium, potassium, zinc, and Vitamins A, B6, and C.
Grow Beets in Containers: Plant beet seeds three inches apart in a container that is twelve inches deep. Because each beet seed is actually a cluster of seeds, be sure to thin the seedlings to one per cluster. Thinnings can be added to salads or sandwiches.
What to Watch Out For: Knowing when to harvest. Beet roots are at their best when they are harvested small – between one and two inches across. At this size, they are sweet and tender. Larger beets tend to be kind of woody and less flavorful.
8. Leaf Amaranth
Leaf amaranth is a less-common vegetable that is well worth a try in your own garden. The leaves have a sweet and slightly tangy flavor that works well in a variety of dishes, from stir-fries and soups to simply steaming it all by itself. As a bonus, leaf amaranth is one of the few heat-tolerant greens. It won’t bolt in the heat of summer the way spinach and kale are prone to. Nutritionally, leaf amaranth is very high in calcium, iron, magnesium, phosphorous, potassium, riboflavin, zinc, and Vitamins A, B6, and C. Everyone should be growing this!
Growing Leaf Amaranth in Containers: Scatter the tiny seeds over the soil’s surface in a pot that is at least 8 inches deep. Harvest the leaves when they are two to four inches tall. You will be able to get at least two or three harvest before you’ll have to sow more seeds.
What to Watch Out For: Leaf amaranth is fairly easy to grow, and relatively problem-free. Rarely, leaf miners can become a problem.
9. Carrots
Carrots are at their sweetest, crunchiest best when freshly harvested from the garden. These icons of healthy eating deserve their “good-for-you” rep – they’re very high in fiber, manganese, niacin, potassium, and Vitamins A, B6, and C. Their only drawback is that they do tend to be high in sugar, so if you’re watching your carb intake, you’ll want to limit the amount of carrots you eat.
Grow Carrots in Containers: Sow carrot seeds two to three inches apart in a pot that is at least twelve inches deep. Look for shorter varieties, such as ‘Thumbelina,’ or ‘Danver’s Half Long.’
What to Watch Out For: Harvesting at the perfect size. Carrots are at their tastiest when harvested small. Leaving them in the ground too long can result in overly large, woody carrots. You’ll also want to make sure to keep your carrots evenly moist, as letting the soil dry out too often can also result in somewhat bitter, fibrous carrots.
10. Leafy Greens
OK, I cheated here. I can’t recommend just ONE leafy green, because they are all incredibly good for us, as well as delicious — kale, collards, spinach, turnip or dandelion greens — how can you possibly choose just one? In general, the “green leafies” contain high amounts of calcium, iron, potassium, and Vitamins A, B6, and C.
Grow Greens in Containers: Grow one kale or collard plant per ten inch deep pot. Other greens can be grown a few plants to a pot — they should be planted at least 4 inches apart and harvested small.
What to Watch Out For: Heat and cabbage worms. Most leafy greens are cool-weather crops, so they’re best grown in spring and fall in most areas – hot weather will cause them to bolt. In addition, many of these greens are members of the Brassicas family, which means they are prone to cabbage worm infestations. Control them with the same methods outlined in the “Broccoli” section, above.
Try growing one or two (or all!) of these nutrient-dense, delicious vegetables in your own garden, and you’ll get double the health benefits: healthy food and time spent outdoors, nurturing your plants
