Author: Monica Reinagel, MS, LD/N, CNS

The pizza looks delicious, bubbling with cheese and studded with pepperoni. And then you see the caption: “A 165-pound woman has to jump rope for 45 minutes to burn off the calories in two pieces of pepperoni pizza.”  Four more slides show similarly decadent foods and the exertions required to negate their caloric content. These arresting images accompanied CNN.com’s coverage of a study recently published in the American Journal of Public Health. As CNN reported, “The number of calories in a food or beverage item doesn’t mean much to many folks. But showing people how much activity they would have to…

Q. Thank you for your recent podcast episode on artificial sweeteners and their possible effects on gut bacteria. You mentioned that stevia may be a good option but what about erythritol?  A. You’re not the only one to wonder! Many new sugar-free sweeteners are a blend of stevia and erythritol, which is a sugar alcohol. Many listeners wrote to ask whether the effects of erythritol are known. Although stevia may support beneficial bacteria, it appears that erythritol promotes neither “good” nor “bad” intestinal bacteria. Researchers found that erythritol is resistant to fermentation by a range of microbiota from human guts. This is…

Q. Hello! My family just returned from Hawaii, and I was excited to try a recipe for Kalua Pork until I saw liquid smoke listed in the ingredients. Is liquid smoke safe? A. Liquid smoke is made by passing wood smoke through a chamber where the vapor is captured and condensed. Along with authentic smoke flavor, the resulting liquid also contains polycyclic aromatic hydrocarbons (PAHs), which can be carcinogenic. The amount of PAHs in liquid smoke depends on the type of wood and the smoking temperature, but the amounts are all quite small. Although I wouldn't drink the stuff, I…

Stephanie writes, “If you need to overhaul your diet, are there some principles that are more of a priority? What’s the best order to tackle the changes needed to rebuild a healthy diet?” I love this question because it shows that—even if her diet needs a total overhaul—Stephanie understands three very important things: 1) building a healthy diet is an ongoing process, not just a decision; 2) trying to change everything at once is likely to backfire, and 3) some things are more important than others. It’s also a great topic for us to explore. Of course, it’s a little…

Nutrition Diva listener Jeffrey writes: “I feel like I get plenty of fiber, but I recently heard that blending fruits in a smoothie destroys the insoluble fiber. Am I defeating my health goals by blending the fruit?” This is a question I get a lot–which is not surprising when you consider the popularity of smoothies and juicing. But I get an equal number of emails from listeners who have heard that blending fruits and vegetables ruptures the cell walls and makes the nutrients more absorbable.  So which is it? Does liquifying your fruits and vegetables make them more nutritious or less?…

Nutrition Diva reader Thomas writes: “Some people claim that the body can’t absorb more than 20-30 grams of protein at a time. Others insist that your body utilizes all the protein you take in. Who is right? Is a post-workout shake with 50 grams of protein a waste?” This idea that the body can only utilize a certain amount of protein at one sitting has become widely accepted nutrition lore.  But is there any validity to the claim? It all comes down to what exactly you mean by “utilizing” protein. This notion about protein seems to have gotten started on…

Q. In your article on decaffeinated coffee, you say that "Almost all decaffeinated coffee is produced using a Swiss water process or carbon dioxide extraction, both of which are quite harmless.” I have heard that Starbucks uses a chemical process to decaffeinate their coffee and I understand this is harmful for us and the environment. What are your thoughts on this? A. After receiving your email, I got in touch with Starbucks and was surprised – and disappointed – to learn that they do, in fact, use a solvent called methylene chloride to produce all but two of their decaffeinated coffees.…

Carrageenan has been the subject of a lot of controversy and several of you have asked me to comment. For those who may not be up to speed on the topic, let me start with a quick overview. Sponsor: Want to save more, invest for the future, but don’t have time to be a full-on investor? Betterment.com helps you build a customized, low-cost portfolio that suits your goals. Learn more. What Is Carrageenan? Carrageenan is an extract from a red seaweed commonly known as Irish Moss. This edible seaweed is native to the British Isles, where it’s been used in…

Mosquitoes find their victims by smell. Specifically, their sensory organs are trained to zero in on sources of carbon dioxide and lactic acid because these chemicals lead them to warm-blooded animals, like you and me.  Chemical repellents like OFF! repel mosquitoes, but not because mosquitoes don’t like the smell of these repellents. Rather, it’s because the chemical DEET is very effective at masking the smell of carbon dioxide and lactic acid. When you’re wearing DEET, the mosquitoes can’t smell you and so they leave you alone. Natural repellents like geranium oil or citronella work the same way, they just don’t seem…

Although I don’t drink much soda (or, as they call it where I grew up, “pop”), I do enjoy drinking sparkling, or carbonated, water and often recommend it as a healthful alternative to soda.  But several of you have written with concerns that drinking carbonated water might be bad for you. Is Carbonated Water Bad for You? Sure enough, I did a quick Internet search and found several websites warning that drinking carbonated water will leech calcium from your bones, causing osteoporosis. Others claimed that carbonated beverages can harm the enamel on your teeth, irritate your stomach, or even cause…