Smoothies are hard to resist: They’re creamy and delicious and have seductive names like “Razzmatazz” and “Berry Lime Sublime.” Plus, they’re everywhere – on the grocery-store shelves, at to-go counters, at special juice and smoothie bars in well-traveled locations – even at the airport. Full of health-and-energy-boosting goodies, smoothies are touted as an ideal snack choice for the health conscious.
Thanks to smart marketing and a genuine desire on the part of the American public to eat healthier, smoothies have become a bigtime operation, with sales topping $1 billion a year, according to Food Management magazine. They have carved out a unique niche in the health and fitness category by presenting themselves as a terrific post-workout snack, a healthy alternative to other forms of fast food and an easy way to help get some of your recommended daily servings of fresh produce.
On the surface, all this may be true. Many smoothies are made with whole fruits, fresh fruit juices, healthy nuts and low-fat, cultured yogurts. Some offer the addition of protein powders, superfoods and other supplements – including vitamins, minerals, herbs and amino acids – that promise to help augment nutrition, burn fat, build immunity, battle stress and reduce fatigue.
Smoothies offer a lot in a nice, portable package. Look under the lid, though, and you may find some things you don’t expect, including up to a whopping 500 calories a serving – almost a quarter of the average person’s recommended daily intake. You might also find giant supplies of syrups and sugars (simple carbs) that can spike blood glucose; artificial sweeteners, flavors and preservatives with questionable health profiles; pesticides and herbicides from chemically farmed produce; and commercial bases of frozen yogurt, sherbet and ice cream that turn smoothies into little more than cleverly concealed shakes. And what about those supplement powders and “boosts” that many vendors add? They generally promise far more than they can realistically deliver and, in some cases, may even interfere with medications.
Perhaps the greatest concerns surrounding smoothies are their high calorie and sugar counts.
“Some smoothies, specifically grocery-store brands, add a lot of extra sugars,” says Cherie Calbom, MS, a clinical nutritionist and author of The Ultimate Smoothie Book (Warner Books, 2001). “And most of them use pasteurized juices that have been heated, killing many nutrients. What’s left is primarily sugar and water.”
The worst juice-bar offenders are generally those made from frozen yogurt and sherbet bases, many of which contain high-fructose corn syrup or sugar as a leading ingredient, and which may also contain chemical stabilizers and texturizers. Smoothies made mostly from all-natural fruit juices, although healthy in that they don’t contain any additives, may still be high in sugar.
It’s the high sugar that makes smoothies so appealingly sweet, of course, but to your metabolism, those same sugars can make a smoothie largely indistinguishable from a soda or milk shake – particularly if you choose one of those vat-sized smoothies currently selling faster than Frappucinos. Such big helpings of sugar send blood glucose levels spiking, causing the pancreas to produce a flood of insulin in response. Because there’s not enough fiber, protein or fat in most smoothies to slow down the digestive process, soon after the sugar spike comes the crash, which can leave you craving more sugar.
Not only is this cycle a setup for weight gain and insulin resistance (also known as metabolic syndrome, a precursor to type 2 diabetes), it can also do a number on your appetite just a couple of hours later. “In the end,” says Jana Klauer, MD, a New York physician who specializes in weight reduction and nutrition, “you might feel hungrier than you were before drinking the smoothie.”
OK, so they present a bit of a caloric quagmire. But at least they’re nutritious – aren’t they? Here, too, experts say, it pays to adjust your expectations. In general, you’re better off with most smoothies than with, say, a bag of chips. But they’re typically nowhere near as healthy or sustaining as a well-balanced meal. And unless they are based mostly on fresh, whole-food ingredients, they may contain fewer nutrients (and far more calories) than a decent nutritional bar.
Smoothies can play a supporting role in a healthy diet and lifestyle – particularly as an on-the-go breakfast, afternoon snack or post-workout replenisher – but they are not ideal replacements for most regular meals. You also have to separate the supposed health benefits from the hype, particularly when it comes to nutritional claims arising from nonfood sources.
Don’t be fooled, for example, by claims suggesting a smoothie can offer a day’s worth of certain essential minerals in just one serving – especially calcium. According to Klauer, this is just plain unrealistic. “You can only absorb a certain amount of a mineral like calcium in one sitting,” she says, “so it’s misleading to advertise a drink as capable of providing 110 percent of the recommended daily allowance.”
Many retail chains advertise “power boosts” or “energy boosts” based on herbal ingredients that have not been evaluated by the Food and Drug Administration or whose claims are widely disputed, says Klauer. Chromium picolinate, a popular diet supplement, has long been credited with building muscle tissue, enhancing athletic performance and aiding in weight loss. But Klauer says that, except in chromium-deficient individuals, clinical results are still inconclusive. As a result, she believes many chromium-boost claims are misleading and overstated.
Other much-touted smoothie additions have received similar so-so reviews from scientists. For example, Jamba Juice, a national chain, claims that its “energy-boost” smoothie contains a “potent combination of ginseng and ginkgo biloba, rhodiola and guarana that help fight fatigue, increase stamina and boost energy.” But the research is still sketchy. While there have been some studies to support these and other herbs’ claims of therapeutic benefits, for the most part, Western medicine has yet to sign off on them with confidence.
Possible side effects pose an additional concern. Although some research has shown that ginkgo biloba might slow the progression of dementia (chronic loss of one’s mental capacity) by increasing blood flow to the brain and possibly reducing mental fatigue, the herb may also trigger headaches and gastrointestinal problems in some people. Guarana increases energy levels because it’s a form of caffeine, but like all caffeine it may also cause side effects, such as restlessness, nervousness and insomnia.
The other problem with herbs in retail smoothies is that you can’t be sure of their quality. According to a recent study by the Medical College of Wisconsin (American Journal of Obstetrics and Gynecology, May 2003), ginseng is often impure: All varieties of ginseng extract are extremely expensive, which means that the cheaper forms often sold in retail health-food products are most likely mixed with other herbs.
Since many herbs are forms of medicine, it’s smart to consult your health professional before ingesting them, particularly if you’re taking any prescription medications – especially antidepressants and certain heart medications, with which they may react negatively.
So is it time to give smoothies the boot? Not necessarily. The solution is to investigate and select your smoothies carefully, or to make them at home so you can control both serving size and quality while reducing cost. A few tips …
Whether you are making or buying, choose organic produce and ingredients whenever possible, both for superior taste and higher nutritional content. A study published in the Journal of Applied Nutrition (Vol. 45, No. 1, 1993) found that organically grown produce can contain over 90 percent more of the nutritional elements found in similar commercial food.
If you’re buying packaged smoothies, read the ingredient and nutrition labels carefully. Check the number of servings in each package and avoid products with lots of added sugars, syrups, hydrogenated oils and additives. Needless to say, you should probably also look askance at smoothies in flavors like “cheesecake,” “caramel” and “banana split.”
When frequenting a particular retail chain, ask to see the ingredient and nutrition labels for any commercially prepared yogurt, sherbet and flavor-base mixes. Choose plain, cultured yogurts when possible. Apple-juice bases might be somewhat less caloric but are generally still high in sugar and, unless they’re organic, may also contain unhealthy chemical residues.
If you decide to go the home route, start with a good, whole-foods-based recipe: 1/2 cup frozen berries (a combination of blueberries, raspberries and strawberries is delicious), 1/2 a banana, and 1/2 cup cold purified water or three to four ice cubes made from purified water (depending on how icy you like your drinks). From there, for protein and texture, you can add a 1/2 cup of natural, cultured yogurt or soymilk (choose the fat and sugar content that suits you) and a handful of nuts or seeds; see “Smart Smoothies” (page 26) for more suggestions.
Finally, whatever you put in, keep in mind that because smoothies go down so easily, it’s easy to “overdrink” them. So, particularly if you’re watching your weight, it’s a good idea to track how much nutrition and how many calories you’re putting into the blender. Also keep in mind that your smoothie doesn’t need to be milk-shake sweet to taste good. Experiment with getting additional flavors by adding and rebalancing other ingredients.
Above all, avoid the temptation to supersize – both at home and at the store. No matter how healthy they are, smoothies ingested in “Big-Gulp” servings tend to deliver big-gut results.
Clearly, it doesn’t take a culinary genius to throw a bunch of stuff in the blender and hit frappe, but by balancing your ingredients for nutrition, energy and hunger satisfaction as well as flavor, you’re likely to get smarter results.
Here are some basic suggestions to get you started:
Whenever possible, use real fruit (not fruit juice) as the base for your smoothies. You’ll get greater nutritional value (including cancer-fighting antioxidants and phytochemicals), plus more fiber and hunger satisfaction, with fewer sugar-based calories.
You can use a combination of frozen and fresh fruit as available and in season. Frozen berries and peaches actually improve the texture of smoothies and are easy to keep on hand. You can peel, slice and freeze bananas, too. Choose organic fruits whenever possible, and carefully wash all fresh produce (including bananas and citrus) to remove bacteria and chemical residues before handling. Pre-chunk larger fruits to facilitate blending. If you’re watching your caloric intake, consider using only half a banana and throwing in some extra blueberries or raspberries, both of which offer an extra dose of fiber and antioxidants and relatively little sugar. Forget about fruit from cans – it’s generally packed in syrup and heated during processing.
- Peaches or nectarines
- Oranges or tangerines
- Cucumbers (yes, they’re officially a fruit)
Nuts and Seeds
While nuts also supply healthy protein and omega-3 oils, a tablespoon or two in your smoothie helps satisfy hunger and ensures a slower, steadier release of energy. Nuts and seeds are high in calories, but they also pack a big nutritional punch. For example, almonds are not only an excellent source of “good” fat and protein, they also provide a healthy dose of vitamin E, calcium, magnesium and potassium. Sesame seeds provide lignan and other proven cancer-fighting phytochemicals, and flaxseeds not only offer fiber and omega-3s, they can also help lower your cholesterol and protect against heart disease and colon cancer. Nuts and seeds also give your smoothie a nice texture, encouraging you to “chew” it a bit, thus catalyzing the enzymes in your saliva that help facilitate the digestive process.
- Pecans or almonds
- Walnuts or cashews
- Peanuts (officially a legume)
- Sunflower or sesame seeds
- Unsweetened coconut
More Protein Sources
One of the most attractive aspects of smoothies is that they allow you to work protein into the first part of your day – a key to stable energy delivery. Yogurts with active cultures (like acidophilus) also provide you with a natural source of healthy probiotics. There are some advantages to choosing a low-fat or even full-fat yogurt over a nonfat variety, namely that the texture and flavor tend to be better, so you can use less and get away with adding less sweet stuff. You net out at about the same caloric intake with a better balance of protein, carbs and fats, and a more appetite-satisfying result. Avoid yogurts with artificial flavors or dyes.Adding a little protein powder to your smoothies is another way to get a good dose of protein, but strive to find one that’s highly digestible and low on sweeteners and other additives. Soymilks and nut milks are highly processed and tend to contain added sugars, but they are a nice alternative for lactose-intolerant and vegan folks.
- Almond milk
- Protein powder
Smoothies are a great vehicle for nutritional supplements you’d otherwise forget to take or tend to avoid swallowing, such as fiber, fish oil and other liquid essential-fatty-acid blends. Spirulina and other green “super-foods” offer terrific nutritional profiles and may assist your body with detoxification and elimination, but they tend to have a strong flavor and give your drink a muddy color, so start with a teaspoon and work your way up. Bee pollen (which doesn’t alter a smoothie’s taste) contains B-complex vitamins, vitamin C, amino acids, enzymes and other minerals.When adding nutritional supplements to your smoothies, avoid megadosing (your body can only absorb so much of any given nutrient at one time anyway), and don’t add so much of any strong-tasting supplements that you wind up having to choke down your drink. Also consider taking fiber supplements separately, as most quickly turn gelatinous and unappetizing.
- Liquid essential-fatty-acid (omega-3 oil) supplement
- Spirulina, chlorella and other “super-greens”
- Bee pollen
During exercise, the body’s primary fuel is muscle glycogen, and the ability to rapidly replenish glycogen during recovery helps build muscle tissue, according to sports nutritionist Suzanne Steen, DSc, RD, head of Sports Nutrition Services at the University of Washington in Seattle. Consuming carbohydrates after you exercise speeds up muscle glycogen resynthesis during the initial few hours of recovery, says Steen, and several recent studies suggest that consuming a small amount of protein (about 3 to 4 grams) along with carbohydrates might augment this response.
A smoothie can be just the ticket to help fill this carb-protein need, because it’s quick and easy and can be custom tailored to contain exactly what your body craves. “Liquids also make an ideal post-workout food,” Steen points out, “because many people don’t feel hungry right after a hard workout. A smoothie goes down easier and it contributes to hydration.”
Smoothies can also lend a hand before you work out. Steen suggests that a pre-exercise meal is just as important as your post-workout one. Drinking a small, relatively high-carb, low-fat smoothie (about 200 calories) an hour or so before a workout can provide your body with energy it needs. “This will also allow enough time for adequate digestion and absorption,” notes Steen, “so your blood will be available to help muscles function properly instead of being occupied in the digestive tract.”|
Making an at-home version of your juice-bar favorite is not only less expensive and better tasting, it’s likely to be lower in sugar and calories and far more nutritious. Keep in mind that the 24 oz. serving sizes below are enough to serve two. For more delicious suggestions, check out Super Smoothies: 50 Recipes for Every Lifestyle by Mary Corpening Barber, Sara Corpening Whiteford and Jan Newberry (Chronicle Books, 2000).
Jamba Juice Peach Pleasure
24 oz., 460 calories
Carbs: 108 g; protein: 4 g; fat: 2 g
Ingredients: peach juice blend, orange sherbet, frozen peaches, frozen bananas, ice
Do-It-Yourself Organic Version
24 oz., 300 calories
Carbs: 61 g; protein: 7 g; fat: 2 g
Ingredients: Typical Cost:
4 oz. organic peach nectar $.50
3/4 cup frozen organic peaches $1.25
1/2 organic banana $.45
1/2 small organic orange $.30
1/2 cup organic low-fat yogurt $.32
1/2 cup water (and ice to taste) N/A
1 tsp. zested orange peel N/A