A whole lotta shakin' goin' on: used in moderation, shakes can be a healthy addition.

Despite up-to-the-second conveniences, Americans routinely say that they don't have enough time to do the basics--eat healthfully, get enough sleep and relax with family. And marketers have convinced us that we will have all the time in the world if we just forego all that silly cooking and fill our shelves with convenience foods instead. Of course, these foods are often more processed and less healthy for us, but they don't always need to be. Using a shake as a meal replacement can be a safe way to manage weight, and get vitamins and nutrients you may overlook at other meals.

"Use in moderation" is the mantra that the vast majority of nutritionists and health professionals attach to meal replacement or snack shakes. But when you do choose to include one, there are hundreds available. Some can be bought pre-made in disposable containers for the greatest convenience (but the biggest expense), and others can be made from powdered mixes, or from scratch with your blender, which is typically the cheapest option. It's easy to "healthy them up" with some basic additions, and many already have enough supplements and health-promoting ingredients to make any health-nut happy.

Lisa Tartamella-Kimmel, a nutritionist with the Yale-New Haven Hospital, says, "It's better to have a shake than going to the vending machine or skipping a meal." Though she adds, "While most shakes and shake mixes have cleaned up their act nutritionally it's still important to make sure you get two 'real' meals a day if you have a meal replacement." That's because it's important for your body to go through the process of digesting whole foods. More than one shake a day might be popular for weight-loss, but should only be undertaken as a diet plan under a doctor's supervision. Also, many shakes are considered dietary supplements, and are not regulated by the Food and Drug Administration (FDA), which means that any claims on the package aren't necessarily supported by scientific research.

Break Your Fast

A popular time for consuming a shake is in place of breakfast. An American Heart Association survey reports that 13 percent of women and 16 percent of men skip their morning meal, and this can lead to lower energy throughout the day; as well as unhealthy blood-sugar fluctuations. Nutritionists and health advocates from Andrew Weil to the late Dr. Atkins are in agreement over the idea that it's not healthful to skip breakfast, and several studies have pointed out that people who skip their first fuel-up tend to be heavier than their counterparts who stop for a morning munch.

If you've wanted to try a shake for breakfast or another meal, but have been intimidated by the varieties of shakes, shake mixes and add-ins, you're not alone. Nutritionally, there are just five things to really look out for and you'll have the basic building blocks for a great shake.

Label Detective

Tartamella-Kimmel advises picking up whatever shake or shake mix sounds good to you and looking at the label before anything else. "First look to see how many calories are in it and check the serving size (there could be two or more servings in a container). Depending on your intention, whether replacing a meal--in which case something with substantial calories might be OK--or as a snack, when you'd want something lighter, make your choice, then incorporate it into the context of your overall diet."

Look for something that is low-fat to begin with, or, if you are directed to add milk, soymilk or yogurt to it, make sure you pick skim or one percent (or light soymilk) to limit your saturated fats. "Look at the total carbs. If sugar or a sugar derivative is at the top of the list of ingredients, it's probably high in refined carbs, which should be avoided," says Tartamella-Kimmel.

You're going to be replacing solid food with a liquid, so consider that most of the pre-made shakes (with a few notable exceptions) are not very high in fiber. If you make a shake yourself, add some fresh or frozen fruit, especially berries, which are low in calories, very flavorful and add lots of fiber. Fiber will help you feel full and aid in weight loss if that's a goal. Hemp seeds, wheat germ, flax seeds or ground nuts are also great ways to add heart-healthy antioxidants, good fats and fiber. Look on the label for ingredients like oat, wheat or rice bran, dried fruits and guar gum if fiber is a concern. Additionally, make sure you get lots of fresh leafy greens, whole grains and other sources of fiber in your non-shake meals to keep your digestive tract happy.

Protein is the last piece of the healthy shake puzzle. The majority of shake mixes and some pre-made shakes get their protein from soy, though many others use dairy as a base (usually in the form of whey, which is protein derived from milk that is separated out), and some use an egg base. (Avoid adding raw eggs to shakes due to the risk of salmonella poisoning.) Soy protein is high in phytochemicals, which the FDA has concluded may reduce the risk of heart disease if consumed along with a diet low in saturated fat and cholesterol. But this kind of protein may not be for everyone (see "Sorting out Soy," Eating Right, July/August 2002). Rice protein isolates are also available for those with soy allergies or for those who would rather limit soy in their diets.

But Make It Just For Me!

After you've covered the nutrition basics, there are still lots of drink options, in a huge variety of flavors and textures, from fruity to chocolaty, to nutty or coffee-flavored.

There are also shakes and mixes made for every lifestyle or health concern. Women may want to look for shakes with added calcium and vitamin D. Older people and those with cancer, diabetes and other diseases tend to have special difficulties getting all the nutrients they need from their food, so super-fortified shakes made especially for those folks, like Ensure (six eight-ounce bottles for $8.99), can help them fill the gap. Vegans will certainly be able to find suitable shake mixes that are based on soy or rice protein rather than whey or eggs.

There are also additives designed to help you achieve weight loss, such as the natural metabolism boosters willow bark, pyruvate and chromium picolinate, as well as caffeine. For years, athletes and those looking to gain muscle have consumed high-protein shakes.

Health food stores are also increasingly stocking "natural" shake mixes, such as Spiru-Tein ($19.99 for 1.2 pounds), which provides a balance of fats, carbs and proteins and is made from non-genetically modified soybeans. Spiru-Tein also includes such goodies as spirulina (a protein source and purported immune enhancer), bee pollen, papaya and bromelain for digestion, and bran, cellulose and apple pectin for fiber. All GeniSoy powders ($17.99 for 16.2 ounces) contain soy protein from soybeans processed through the Identity Preservation Program (IPP Certified), a certification program guaranteeing non-GMO soybeans.

Anatomy Whole Food Mixative from Intelligent Nutrients (see Tools for Green Living, this issue) is 100 percent organic, high in fiber and is made from whole foods, including soybeans, flax seeds and broccoli sprouts instead of the more conventional protein, vitamin and mineral isolates. Some natural health practitioners believe whole food ingredients provide more reliable nutrients.

Stonyfield Farm makes yogurt-based smoothies ($1.49 to $1.89 for 10 ounces) with inulin, a natural fiber source, lots of calcium, and six live active cultures. Westsoy makes tasty soymilk smoothies ($1.99), which are great as a snack and also Vigoraid, a meal replacement, with added vitamins and nutrients. CONTACT: Ensure, [phone], www.ensure.com; Genisoy, [phone], www.genisoy.com; Intelligent Nutrients, [phone], www.intelli gentnutrients.com; Spiru-Tein, www.na turesplus.com; Stonyfield Farms, [phone], www.stonyfield.com; Westsoy, [phone], www.westsoy.biz.

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