by Carole Jackson, Bottom Line Health
Talk about a dream team: There are two anti-inflammatory substances in broccoli that come together when we eat it to help us fight killer diseases such as cancer and heart disease. The trouble is, when we cook broccoli for too long, we unknowingly neutralize substance A — and substance B canât work without its partner. One healthful solution would be to eat broccoli only raw — I donât know about you, but thatâs not a thrilling idea to me. Another solution would be to lightly steam broccoli for no more than two to four minutes to preserve its nutrients, but getting the timing just right while youâve got three other things cooking isnât always easy. So I was delighted to see that a new study has found that you can fix this problem a third way — by simply eating a certain other kind of vegetable along with your nicely cooked broccoli. While other studies have shown that overcooking broccoli disables its disease-fighting power, this is the first study that shows a way to get some — or even most — of that power back.
Interested in hearing more about this disease-fighting veggie duo, I called Elizabeth Jeffery, PhD, a professor of nutritional sciences in the College of Agricultural, Consumer and Environmental Sciences at University of Illinois in Urbana-Champaign and a coauthor of the study.
GET THE MOST BANG FOR YOUR BROCCOLI
Dr. Jeffery called the disease-fighting compound that we want from broccoli “SF” — thatâs short-hand for sulforaphane, which youâve no doubt heard of for its anti-cancer and anti-heart disease benefits. But the SF isnât just sitting around in the broccoli waiting for you to eat it — it has to be created when an enzyme called myrosinase (substance A) removes a sugar molecule from a larger molecule, glucosolinate (substance B), and frees up the SF. Chewing breaks up the broccoli cells so that substance A and substance B come into contact and produce SF. The glitch occurs when cooking broccoli, because the enzyme myrosinase is destroyed by heat — so no SF can be produced.
For this research, Dr. Jeffery studied four healthy men between the ages of 18 and 30. The men were each fed one of four different food combinations every six days for 24 days. One control meal was cereal and yogurt, another meal was cereal and yoghurt with Â½ teaspoon of broccoli powder (which has no myrosinase), a third was cereal and yogurt with four teaspoons of fresh, raw broccoli sprouts (which do contain myrosinase) and the fourth meal was cereal and yogurt with a combination of the powder and the sprouts. To see just how much SF each meal produced, the mensâ blood and urine were tested just before they ate each meal and then again six, 12 and 24 hours afterward. To keep other factors from affecting the results, the men were given a list of foods that contain glucosolinates and were told to avoid these foods for three days before the study and during the study. The men were also told to avoid dietary supplements and to limit alcohol to no more than two drinks per day.
The results: Out of all four meals, the combination of broccoli sprouts and broccoli powder produced the highest levels of SF in the body, which suggests, said Dr. Jeffery, that eating a myrosinase-containing food along with your broccoli can bring back the broccoliâs disease-fighting properties — even if you cooked the myrosinase out of the broccoli.
That second food doesnât have to be broccoli sprouts, but it should be something raw (since cooking the second veggie would destroy its myrosinase too), said Dr. Jeffery. So if youâre not a big fan of sprouts, you can choose among these other veggies for a similar effect, she said: radishes, mustard seeds and greens, arugula, watercress, wasabi root and leaves, cabbage and horseradish. Phew. I donât know about you, but Iâm so glad that I donât have to give up cooking my broccoli.
Elizabeth H. Jeffery, PhD, professor of nutritional sciences, College of Agricultural, Consumer and Environmental Sciences University of Illinois at Urbana-Champaign.