If the winter frost is sending you indoors for too much sloth and sleep, you might find yourself turning to green drinks for a dose of vigour.
We're talking here about those jars of powder containing everything from dehydrated wheat grass juice and sea vegetables to herbal extracts and colon-friendly bacteria. It can be taken in capsules or mixed with liquid.
These mixtures are marketed as cleansers and energy boosters, and recent research backs some of the hype. Still, don't mindlessly chug them.
You shouldn't let anyone sell you the stuff because you're sick. Many green drinks contain herbs and other ingredients that can interact with medications and other herbs. And if your body is burdened with a toxic load, the cleansing effects could be too rough. The bottom line? If you're not basically healthy, consult with a practitioner before guzzling.
If you've got allergies, be aware that some of these compounds contain bee products. Even wheat or barley grass extracts might cause reactions if you're super-sensitive to grains.
If you're taking both herb formulas and a green drink that contains licorice, make sure you're not inadvertently overdosing yourself with that herb, which can cause high blood pressure.
Some people who use green supplements also cycle on for three to four weeks, off for one or two weeks, to avoid herbal overexposure. There's no research yet indicating whether their concern is real.
Green drinks definitely have antioxidant power that helps stop cell damage due to stress, pollution and poor diet. But brands vary in effectiveness, because of the quality of the raw ingredients. The experts agree that these products are no substitute for fresh fruits and veggies - you'll get the most benefit from the powdery tonics if you're already eating a healthy diet.
What the experts say
"Green drinks act as a safety net. If a person finds it too difficult to achieve five to 10 servings of fruits and vegetables a day, I look at a green supplement. Because green drinks are quite detoxifying, it's best to gradually increase one's intake to avoid side effects such as headaches or diarrhea. Morning is the best time of day to have these, 20 minutes before a meal. That gives you the energy boost that's needed in the morning, and it carries through the day."
PATRICIA GABRYL , naturopath, Toronto
"Green foods contain chlorophyll, beta carotene, minerals - most importantly trace minerals that enhance fat and sugar metabolism - and protein. Some manufacturers accuse one another of having too much fibre in their product as filler. Apple or grapefruit pectin is beneficial for the colon and adds to the cleansing and detoxifying effect of the chlorophyll. Green drinks have an anti-inflammatory effect and the ability to alkalize the body. Many diseases occur because the body is too acidic. They're not as good as real, wholesome food. But they're so much better than prescription drugs."
VIVIAN LEE , registered holistic nutritionist, manager, Canadian School of Natural Nutrition, Toronto
"Independent testing has found big differences in the antioxidant activity of various products. That's likely a result of choices made at the supplier level. A consumer can call the company and ask, 'What's the ORAC (a measure of antioxidant activity) score on this?' Decent ORAC scores are 50(mmole TE/g) or higher. A top-notch green drink comes in at 320. The most alkaline-forming vegetable is spinach, and a top green food product has double that alkalizing ability."
ALAN LOGAN , naturopathic, consultant to ehn inc., makers of Greens+
"As a pharmacist, I was skeptical that Greens+ had enough of any one ingredient to have a clinically significant effect. There was an assumption that synergy existed between the ingredients, but no research. The results of our findings were positive but not conclusive that Greens+ increases vitality and energy. People taking it had higher energy than those in the placebo group, and the difference was statistically significant. The Greens+ group also scored higher on the vitality scale, but the difference didn't quite reach statistical significance. We questioned whether, if the trial had been longer, we might have seen a statistically significant difference; we don't know. I'll be honest, though. The results were far more positive than I expected."
HEATHER BOON , assistant professor, Leslie Dan Faculty of Pharmacy, University of Toronto
"Drinks with herbs may be too stimulating, or may interact with medications. Generally speaking, green foods contain magnesium and vitamin K. Some people, if they get too much magnesium, may get diarrhea. In people who have had strokes or heart attacks, vitamin K might work against their medications. Some might be using these to avoid their five servings of fruits and vegetables a day, and it's never been proven that these drinks work that way. I do recommend them to people who are under stress and don't eat properly. I don't think they're a bad thing, but they're not a panacea."
ZOLTAN RONA , MD, MSc