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…

When I was growing up, there were only two kinds of olives at the grocery store: green olives stuffed with pimentos and pitted black or “ripe” olives that you could wear on the tips of your fingers until your Mom made you stop playing with your food. Today, of course, most grocery stores have entire olive bars, with all kinds of exotic varietals—everything from the tiny brown Nicoise to the giant, bright-green Cerignola, to the shriveled black Morrocans. But “are they all the same nutritionally?” asks Grace. “Or are some types particularly good for you?”  Meanwhile, Tania wonders how olives…

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…

I’ll bet that a lot of you are just like me. I wake up every morning with the best of intentions. I’m going to nourish my body with wholesome nutritious foods and avoid junk food and mindless snacking. But sometimes, as the day goes on, I end up going off track. I impulsively order an oversized muffin at the coffee shop. I find myself munching on pretzels or M&Ms at my desk. I get to the end of the day and realize I haven’t had a single vegetable. Of course, we all have those days once in a while. But…