When it comes to our diets, green is gorgeous. The vitamins and minerals that we absorb through green foods such as kale, spinach, broccoli, Brussels sprouts and collard greens helps us to live a longer, better and more beautiful life.

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So where exactly does that vibrant green color come from? It’s from a pigment called chlorophyll, a substance found in various amounts in all plants, including green vegetables. Chlorophyll is just one component in green vegetables that gives them their cancer-fighting properties.

If you’re like many Americans, however, you may find yourself skipping the produce section all together and going straight to the supplement aisle for your “green” powder substitutes. These powders have become a popular ingredient in smoothies as a way to get the great components of green foods without actually having to eat them. The question is, are you still getting the benefits—or just wasting your money? 

Americans spend billions of dollars every year on supplements and yet, we remain some of the unhealthiest individuals in the world. Our incidence of lifestyle-related chronic disease is soaring while our consumption of whole foods is sinking. If you look at the healthiest cultures in the world, found in areas in Italy, Greece and parts of South America, however, they’re eating lots of fruits, vegetables, nuts, legumes and fish. What they are not popping is supplements.

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As a dietitian, I believe that we can and should get most of our nutrients the way our grandparents did: through whole foods. However, I understand that busy lifestyles can often cause us to choose another more convenient option. While a “greens” supplement is better than getting no greens at all, it may not necessarily be the better option for several reasons.

Are You Getting the Right Kind of Gorgeous Greens?

Lack of fiber

One cup of broccoli has a little over 2 grams of fiber. This fiber will help you stay fuller longer, so you’re less likely to reach for the candy bowl midday. Adults should aim for 25 to 35 grams of fiber every day—ideally, from whole food sources. A study in the journal Nutrition found that including dietary fiber in a healthy eating plan was linked to increased success with weight loss and weight maintenance.

On the flipside, the smoothie you’re having with your powdered greens may be loaded with simple sugars that will spike and drop your blood sugar faster than a roller coaster, leaving you wanting more food, sugar and satisfaction.

Zero chewing pleasure

Chewing equals satisfaction and the science is there to back that up. Researchers have found both the rate of chewing as well as the mere act of chewing has an influence on weight in both children and adults. A recent study in the American Journal of Clinical Nutrition found that obese individuals had a higher ingestion rate and a lower number of chews when eating compared to their lean counterparts.

Why does this matter? The obvious reason is that you’ll ingest fewer calories, but the less obvious explanation for this has to do with how chewing affects the “hunger” hormone ghrelin. This hormone is secreted by the gut and communicates with your brain that you are hungry. In this particular study, blood tests taken 90 minutes after eating showed that individuals who chewed 40 times (as opposed to 15) had much lower levels of ghrelin and thus, ate less due to decreased appetite. I’d rather chew my greens than drink them….and it appears that the research agrees!

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Nutrient absorption

Perhaps the most important reason to bulk up on whole foods as opposed to supplements comes down to how much bang for your nutritional buck you’re getting. For example, lightly steaming broccoli and spinach helps to penetrate the cell wall of the plant to extract those beauty-enhancing nutrients for optimal absorption.

What are you actually getting?

Finally, once we venture out of the produce aisle, it’s unclear what additives are in the supplemental forms of fruits and vegetables. While many reputable companies exist, providing high quality supplements to consumers, most consumers can’t identify the good products from the bad. Your goal may be to consume healthy greens, but you may instead end up ingesting a whole slew of additives and fillers instead.

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So is the cost of powdered greens really worth it for your health and your wallet? For now, I say stick with the foods that have been around for thousands of years—whole foods.