How Much Sugar is Too Much for Your Teeth?


Hi, I’m Dr. Rob Karlinsey, an oral health resource for clinicians, researchers, and laypeople alike. When I give presentations about preventive dentistry, which usually involves fluoride and remineralization, I’m often asked several questions. Because I’m finding that some of these questions are frequently asked and are relevant to today, I thought I’d prepare and share with you several unscripted Q&A videos regarding my opinions.

So here’s a question regarding sugar: Is sugar the scourge of dentistry or what?

  1. Answer: As one who grew up needing obligatory fillings practically every year (but hasn’t had a new cavity in over a decade despite a penchant for baked goods) I know more than a little about this. So I’ll throw my towel into the sugar vs. tooth-decay
  2. I’m sure you’ve been told your zeal for ‘sweets’ is the root cause to your tooth decay.
    1. Well, as it happens, that’s not the full story and you don’t have all the information you should.
    2. It’s no secret that casual relationships between sugar intake and tooth decay exist. But thus far, no mathematical equation has been devised that equates eating “X” amount of sugar produces “Y” amount tooth decay.
    3. So why isn’t there an immutable sugar-tooth decay relationship?
      1. Because it’s not only about sugar.
        1. It’s about behavior. It’s about what we eat, how much and how frequently.
        2. And it’s about our oral hygiene regimen and the nature of the products we use.
        3. And it’s about our oral health knowledge as patients.
        4. And, it’s about our personal genetic disposition to tooth decay.
        5. And the list continues.
      2. By the way, tooth decay isn’t just a disease borne from convenience and comfort foods: did you know tooth decay is at least a million years old?
    4. Yes, I realize ‘Big Sugar’ and ‘Big Food’ certainly contribute to the problem. And, it doesn’t help when the desire to embrace progressive change is stonewalled by the very organizations these ‘big bad companies‘ look to for regulatory and public sentiment guidance.
      1. But I’m not debating data, business models, agendas, or moral imperatives.
      2. Why? Because constant pestering and demonizing of sugar isn’t working, may worsen the problem, and it masks underlying issues.
  1. Here are several reasons why sugar probably isn’t the culprit many make it out to be:
    1. Ever been told you can’t or shouldn’t do something? Bet that makes you want to do it.
      1. Formally, this is called Reactance Theory, and is a normal response to those seeking or somehow threatening to take away our right foods. Sugar in particular. It doesn’t end well.
      2. In fact, this is probably the wrong approach. A better approach would be improved and repetitive communication. Effective communication is admittedly challenging, but I’m just pointing out why the lack of it can lead to problems.
    2. Should we abstain from sugar?
      1. Go ahead and let me know how that works for you. I’m not talking about 1 day, 1 week, 1 year or 10 years. I mean for your life in all situations. It’s not only a lifestyle choice, sometimes, we just don’t know. There’s a classic example in the sit-com Seinfeld, where despite swearing off caffeine, Jerry was oblivious to the fact his daily tea was infused with caffeine. Great episode and here the analogy is clear: it’s difficult to know 100% what’s in your food (unless of course you have a trusted, personal chef with strict orders to follow your non-sweet rules).
      2. By the way, don’t cut my carbs – it’s a basic tenant of energy cycle (literally, our existence) that we need carbs to function properly.
  2. You’re unique – just like everyone else.
    1. This is like the Yeti: some people emphatically believe, while others, not so much.
    2. It turns out that beyond structural differences in teeth between those susceptible to tooth decay and those who aren’t, there are also clear differences in the mouth’s microbial makeup of those with and without tooth decay.
      1. Therefore, regardless of the absence or presence of sugar, bacterial composition plays a major role in determining whether the individual is prone to tooth decay or not.
      2. This explains, in large part, why my brother didn’t experience tooth decay. This also explains why the ‘anti-sugar’ message from the dentist has not proven effective: for example, tooth decay is increasing among children!).
    3. The point is, a boilerplate proclamation to avoid sugars resonates differently among people.
      1. While over-consumption of anything (including sugar!) is not recommended, the sensitivity to a given agent (i.e., sugar) is specific to an individual.
      2. Therefore, well-intended warnings that do not always ring true diminish over time, a la Aesop’s tale ‘The boy who cried wolf’. And because tooth decay is a gradual process, the clinician’s warning today may not reveal itself until months – or even years – later.
  1. Sugar is just one of several tooth-risky food/drink characteristics.
    1. The acidity and acid content of the food or drink produce dental damage much more quickly than sugar and starches.
  1. So instead of going 100% sugar-free for all eternity in an bid to have a healthier mug, just remember whatever you’re eating or drinking,
    1. ensure you’re drinking plenty of water;
    2. have a rock-solid oral hygiene regimen;
    3. consider food and drink options with calcium; and,
    4. ensure your behavior with your drink or food isn’t compromising your tooth structure.
2018-03-04T19:16:18+00:002018|Media, Q&A|

Robert L. Karlinsey, PhD

Dr. Robert L. Karlinsey earned a BS in Physics and PhD in Chemical Physics, holds several patents, and has published in multiple fields including dentistry, chemistry, and materials science. His lifelong struggles with his own dental decay ultimately inspired him to investigate the remineralization of teeth.