The Most Frequently Asked Nutrition Questions—Answered

Everyday Medcan’s registered dietitians offer clients expert advice to help them optimize their diet. Over the years, they’ve been asked hundreds of nutrition-related questions, including many that they answer on repeat. In a recent episode of Eat Move Think, dietitians Leslie Beck, Olivia Cupido and Terence Boateng, sat down to dispell myths and share answers to commonly asked nutrition questions.

Q: Which foods should I never eat?

Olivia: I strongly believe that there is not any one food that we should never eat. So I tend to cheat this question with my clients a bit: I’ll say, don’t ever eat something you’re allergic to, or something you really dislike. So that’s my…non-answer, if you will.

Terence: I have my own non-answer as well! When I was a newly minted dietitian, I tried to eliminate all the “fun” foods from my diet. Then one day I threw a house party, and all the guests left behind bags of chips, tubs of ice cream, bottles of pop . . . and I ate almost everything the very next day. So I learned that over-restricting, and never eating certain foods, can have a rebound effect that only makes you feel guilty. Now, to my clients, I suggest making the healthy choice the default choice, and enjoying fun food in moderation.

Leslie: Those are great points. That being said, there are definitely foods that we tell our clients to limit, or to eat sparingly. Sugary beverages are the major source of sugar in the Canadian diet, yet we know that routinely drinking them is tied to a greater risk of type 2 diabetes and heart disease. Processed red meats and ultra-processed foods are other foods we should be limiting our intake of. Are there foods we should never ever eat? I’d say no, but there are certainly some that you should limit.

Q: Is diet pop bad for you?

Terence: For me, this one depends on the client. If I’m working with someone who’s highly motivated and working on finetuning their diet, then absolutely, diet pop is something we’re going to talk about eliminating. But there are clients who have a much wider range of nutrition habits they need to work on, and if drinking diet soda versus full-sugar soda is the one thing they feel good about, then I’m not necessarily going to eliminate it.

Olivia: As a dietitian with a focus on digestive and gut health, I do have a few concerns with artificial sweeteners found in diet pop. A recent 2022 study examined whether non-nutritive sweeteners (sucralose, aspartame, stevia) affect the microbiome, and it provided definitive proof that they do. So diet pop is always on my to-watch list.

Leslie: I’ve been following the studies, too, and many suggest that there are potential health risks associated with consuming even moderate amounts of diet pop. A 2019 European study, for example, found that drinking two or more eight-ounce glasses of pop per day, artificially sweetened or not, was tied to a greater risk of early death—and when the researchers looked and diet pop and sugar-sweetened drinks separately, the participants who drank artificially-sweetened soft drinks actually fared worse. If you’re a daily diet pop drinker, I recommend cutting back. Replace some with sparkling water or flavoured unsweetened carbonated water.

Q: How much coffee is too much?

Terence: There has been research that indicates a modest increase in cardiovascular risk in people who overconsume coffee. But if you look more closely, you’ll see that there are groups of people who can drink plenty of coffee without it having any negative effect on their cardiovascular system. It depends on whether you’re a “slow” or “fast” caffeine metabolizer. The longer caffeine stays in your system, the more it can increase blood pressure. So for a slow metabolizer, I’d recommend limiting intake to 200 mg of caffeine a day—or two small eight-ounce cups. For fast metabolizers, it’s safe to go up to 400 mg without increasing risk.

Olivia: I take a little bit of a different approach on this one (partly because I am a big coffee fan). There is research that indicates that coffee can be supportive to liver health due to its antioxidants. On the other hand, people with gut health issues like IBS may find coffee to be a trigger. I don’t tend to recommend cutting out coffee altogether; rather, I work with a client to identify if coffee is right for them.

Leslie: When people ask me this question, I usually give them good news: there’s plenty of evidence to suggest that drinking three to five cups of coffee a day can help prevent certain chronic diseases. Coffee—regular or decaffeinated—has consistently been found to decrease the risk of type 2 diabetes. I also often need to dispel that myth that coffee is dehydrating. Although caffeine is a mild diuretic, the amount of water in coffee offsets that effect. Coffee counts toward your daily water intake! But I agree, it’s important to consider the client. Excess caffeine can cause headaches, make you irritable or anxious, interfere with sleep and upset digestion. Coffee – regular or decaf – can worsen acid reflux, too.

How many eggs can I eat a week?

Leslie: I can’t tell you how often I get this question. The debate over eggs revolves around their high cholesterol-content (185 mg per one large egg, all in the yolk). Consuming too much cholesterol has been thought to raise LDL (bad) blood cholesterol, an established risk factor for heart attack and stroke. But for most people, dietary cholesterol has little to no impact on blood cholesterol. One egg a day is fine. There are some people, though, who should limit their cholesterol intake. People who have elevated LDL cholesterol, diabetes or existing heart disease—to them I recommend no more than four egg yolks per week.

Terence: I think a blanket approach, like telling people to have only two eggs for breakfast, regardless of whether they have underlying health conditions like high LDL or diabetes, is the wrong message, particularly because of the health benefits of eggs. The personalized care approach is more reasonable; assessing a person’s risk and tailoring your recommendation.

Olivia: Eggs are super nutritious. Right now, I’m pregnant, and the messaging is to eat more eggs because they’re a great source of choline. Pregnant women are advised to eat at least one a day, and some dietitians will recommend more than that! And the data shows that the choline in egg yolks is not only crucial for fetal brain development, but it’s important for everyone in terms of brain health.

If you’d like to arrange a nutrition consultation with a Medcan registered dietitian, email nutrition@medcan.com.