Sitting on a plane a few weeks back an inquisitive fellow passenger helped me write this blog. Her questions weren't unlike others I often get when I tell people I'm a registered dietitian. Hopefully you can benefit from these too.

Can I eat butter? I usually remind people that they can eat anything they want to as long as they do it in moderation. I think readers, clients, patients, and others get tired of hearing "everything in moderation", and I completely understand. However, it really is the truth. Personally, I don't discourage using butter in cooking or baking. Why? I prefer the more natural ingredients in butter and am willing to trade off saturated fat for an artificial product. However, if you can't commit to using it sparingly, then you may benefit from exploring a heart healthier margarine or imitation butter.

Which type of oil is best for cooking? You should look for oils that are high in unsaturated fats (monounsaturated or polyunsaturated on nutrition labels) and low in saturated fat. The top two on this list are canola oil and olive oil. When it comes to olive oil, the difference between virgin, extra virgin, or light is more a matter of preference in terms of flavor. These variations do not change the nutrition facts.

Should I take a vitamin? I typically describe multi-vitamin/multi-mineral (MVI) supplements as an insurance plan for your dietary intake. If you eat a balanced diet rich in a variety of fruits, vegetables, whole grains, lean meats, and low fat dairy, you likely don't need a MVI. However, if your dietary intake is inadequate in terms of food groups or variety, or even if it's inconsistent day to day, then it may be a good idea to take a daily supplement to help fill holes in your diet. With that said, I typically recommend vitamin D supplements even to the best of eaters because it is not widely available in our food supply. For more info on vitamin D, check out this blog.

Is white wheat bread okay? There is white bread, white-wheat bread, whole wheat or whole grain bread, and finally white whole wheat bread. When people ask me about bread, I inevitably end up reviewing the nutrition facts panel and the ingredients panel with them. Why? There are many, many breads out there and certainly some are better than others. It always comes down to what the bread is made of-what exists naturally versus what is added to enrich the bread. When it comes down to it, you really want to see "whole" included in the first ingredient on any bread you buy- as long as it's made from a whole grain, don't judge a bread by it's color.

For example, "white whole wheat bread" simply uses a different whole grain than what we see in "normal" whole wheat (brown in color) bread. It is white in color because it is made with an albino whole grain.

Is a sweetener from the Stevia plant better for me? Not really. It is just the latest sweetener to be put on the market. As with those that have been around for awhile, there is no direct connection between consumption of these sweeteners in moderate amounts and diseases such as various types of cancers. The sweeteners (Truvia, Purevia, Sun Crystals, etc.) are made of components of the Stevia plant so they aren't 100% natural. Besides, FDA lacks a definition for "natural." For more information about different sweeteners, check out this fact sheetfrom the International Food Information Council.

What is the best weight loss pill? This one is tough to answer for the general population. For certain individuals, pharmacological approaches to weight loss may be appropriate, but for most people diet and exercise are still the most effective and safest ways to lose weight. As always, focus on fiber via fruits, veggies, and whole grains!

Tanya Zuckerbrot MS, RD, is a Registered Dietitian in New York City and the author of two bestselling diet books: The F-Factor Diet and The Miracle Carb Diet: Make Calories and Fat Disappear – with Fiber.

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