By Alicia Anskis, M.S., R.D.
Brigham and Women's Hospital
Like most other science fields, nutrition is constantly changing. New research often leads to new dietary advice. And a flurry of trendy products often follows.
In a world full of conflicting health information, how do you know what is valid and what is just the next money-making gimmick?
We researched six of the most popular nutrition trends on the market to help you sort through the hype. Find out whether or not they are worth your money.
What it is: Greek yogurt is made from cow's or sheep's milk that has been strained in a cloth to remove the whey. This results in a thicker yogurt. Greek yogurt comes in two varieties: strained Greek yogurt (the original) and "Greek-style" yogurt (the American version often with added protein and thickening agents (corn starch) to produce a "Greek-like" texture).
Cost: $1 - $2.15 per cup
Health claim: High in protein and probiotics
Evidence: It's true! Greek yogurt is a protein powerhouse. It contains about twice the protein of traditional yogurts. This is equivalent to eating about 2 ounces of meat or poultry. And it still maintains all the gut-friendly bacteria that other yogurts have.
Bottom line: Choose plain or vanilla-flavored to avoid the added sugar in the fruit flavors. We don't know if the body processes the natural, strained Greek yogurt differently than the Greek-style yogurts. So it is probably best to stick with brands that use the more traditional mode of processing (Fage, Chobani, Stonyfield Farm and Oikos).
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What they are: These nutty, edible seeds come from the plant Salvia hispanica, which grows in Mexico and South America. And yes, these are the same seeds that were used to grow the infamous Chia Pet.
Cost: $7 - $19 per bag
Health claim: High in fiber, omega-3 fatty acids
Evidence: This food is high in several nutrients, including calcium, phosphorus, magnesium, manganese, copper, iron, molybdenum, niacin and zinc. It also contains a generous amount of fiber: just 1 ounce (2 tablespoons) provides about 10 grams of fiber (about 30% to 40% of the daily recommendations). It is also a good plant source of omega-3 fatty acids. Unlike flaxseeds (another plant source of omega 3s), chia seeds are much more easily absorbed in their whole form (flaxseeds need to be ground).
Bottom line: Chia seeds are safe to eat. And they have many health-promoting nutrients. They make a great addition to an overall healthy diet rich in fruits and vegetables, lean meats, fresh fish, whole grains, nuts and seeds. There is some evidence that chia seeds may help improve heart-disease risk factors, such as high cholesterol, triglycerides and blood pressure.
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What they are: These are natural compounds that give red raspberries their scent. They were used primarily by the perfume and food industries, but now they are being sold in supplement form.
Cost: $10 - $50 per bottle
Health claim: An aid to weight loss
Evidence: Raspberry ketones have a molecular make-up that's similar to that of the stimulants capsaicin and synephrine. They speed up the body's metabolism. That's why raspberry ketones are promoted for weight loss. However, there have been no human research studies to support this claim. Research that is available has used lab mice, which does not necessarily translate to humans.
Bottom line: Don't waste your money on this supplement. Instead, opt for eating raspberries, which are naturally low in calories and high in vitamin C and antioxidants. Vitamin C helps support tissue repair and a healthy immune system. Antioxidants (flavonoids and anthocyanins) help the body's defense system to combat age-related and chronic diseases.
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Green Coffee Bean Extract
What it is: Raw or unroasted beans of coffee fruits, which are the same beans that are roasted, ground and used to make coffee.
Cost: $10 to over $50 per bottle
Health claim: Promotes weight loss, helps reduce the risk of type 2 diabetes, cardiovascular disease and inflammation in the body.
Evidence: The support for weight loss is limited. It's been suggested that a compound called chlorogenic acid found in coffee beans may help reduce the risk of obesity and type 2 diabetes by inhibiting an enzyme that promotes the formation of glucose in the liver. However, a recent study has shown no such effects of the extracted compound on body fat. In fact, the coffee-been extract was actually more likely to promote fat accumulation in the liver. And that can lead to the development of diabetes over time.
Bottom line: Limit yourself to 1-2 cups of regular coffee per day. You can still get the health perks from the coffee bean's antioxidant properties while saving your wallet, and without having to worry about any potential side effects.
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Aloe Vera Juice
What it is: Aloe vera is a cactus-like plant that is a well-known treatment for skin diseases and for wound healing. More recently, the plant's gel (and sometimes the whole plant) has been added to fruit juices.
Cost: $1.75 - $4 per bottle
Health claim: Improves digestion, reduces constipation, heartburn, inflammation, inflammatory bowel diseases (IBD).
Evidence: Aloe vera gel may be helpful in mild to moderate ulcerative colitis (IBD). One short-term study found that oral aloe vera gel taken for 4 weeks improved GI symptoms in people with IBD. And it also helped to reduce the amount of inflammation.
Other research has shown that whole aloe leaf has a laxative effect in constipation. However, some studies suggest that this substance may be harmful to the kidneys if used long term, particularly in high doses.
Bottom line: There is no clear evidence that this drink helps irritable bowel disease or inflammation. Although drinks containing "whole leaf aloe" appear to be effective for constipation, the potential harmful effects outweigh the benefits. To ease constipation, opt for at least 25 grams to 35 grams of fiber per day. And drink plenty of water.
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What it is: Coconut oil comes from the inside of coconut kernels. It is made up of 92% saturated fat, mainly in the form of triglycerides.
Cost: $8 - $13 per 16-ounce jar
Health claim: Reduces the risk of cardiovascular disease, obesity, Alzheimer's and other age-related degenerative diseases; reduces symptoms of malabsorption.
Evidence: Coconut oil is made up of medium-chain triglycerides (MCT). They are absorbed differently in the body than long-chain triglycerides. So coconut oil can be very effective for problems with malabsorption. Coconut oil has saturated fat, so it was assumed that it was bad for cholesterol and overall heart health. However, due to the MCTs, the body might process coconut oil differently than other saturated fats, like butter and animal fats. Direct studies using coconut oil are scarce, and the research available is conflicting. Additionally, many previous studies used partially hydrogenated coconut oil, which contains unhealthy trans fats. Data that are available have suggested that coconut oil might improve overall cholesterol ratios by increasing "good" high-density lipoprotein cholesterol levels. Overall, it does not appear to be as harmful to health as butter.
Bottom line: More research is needed to confirm the potential benefits of coconut oil. For some people, coconut can be a healthy food if eaten in moderation, but it should not replace other healthy fats like avocado, olive and canola oils. It is important to remember that coconut oil is still a fat and has lots of calories. One tablespoon has 117 calories, 14 grams of fat, 12 grams of saturated fat. It is also important to use "virgin" coconut oil, and to avoid any hydrogenated or partially hydrogenate coconut oils, as these contain trans fat.
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Alicia Anskis, M.S., R.D., recently completed her dietetic internship at Brigham and Women's Hospital. She graduated with a B.A. in psychology from Syracuse University and a M.S. in nutrition from Drexel University.
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