Ask the SugarScientists

The SugarScience team includes renowned health scientists whose work ranges from laboratory research to population studies and clinical care for adults and children. They would be happy to answer further questions about sugar and health.

Type your question in the box below and click "Submit Question." You'll be asked for your name and email, so we can send you a direct response or alert you when we have posted the answer from a SugarScientist. 

We have received hundreds of great questions so far, many of which have sent us back to the medical library for further research. Please know that if it takes us a while to respond, we haven’t forgotten you — we’re just working on getting everyone an accurate answer. Your patience is greatly appreciated! 

Is stevia a safe alternative to sugar?

We ran a search on all of the recent studies of stevia and reviewed them for you.  We found very few peer-reviewed publications on stevia, and our review of those we did find concluded that it's too soon to draw conclusions.  Most of the studies have been done on rats, not humans.  And as we say, the findings are "mixed" – some suggest that stevia has similar negative effects to other artificial sweeteners and others say the opposite.  Mixed results are typical to see in newer areas of research.  A well-documented concern with other artificial sweeteners  (e.g., saccharine, aspartame, sucralose) is that they can increase "glucose tolerance," which explains why use of these products has been linked to weight gain and Type 2 diabetes.  We see studies on both sides for stevia – some saying it does, and others saying it does not, contribute to glucose intolerance.  We're sorry we can't provide a firmer answer to your excellent question and wish the evidence base on stevia was stronger.  Please stay tuned. We will be following the research on artificial sweeteners and reporting what we learn through our SugarScience alerts and on our web site at

Added sugarFAQSubstitute sugars/ flavors/ preservatives

Is it possible to actually gain weight without changing your activity level or caloric intake?

Yes, it is possible! In the film, That Sugar Film, Damon Gameau actually gained weight without changing his activity level or caloric intake.  What happened to him is also happening to millions of Americans who over-consume added sugar, making us the fattest nation on earth.  This was the point that Mr. Gameau was trying to illustrate in the film by doing this experiment on himself—something many of us doing science on health have come to understand based on the evidence.  

This somewhat complex—having to do with how sugar’s damage to the liver leads to changes in hormones in the body.

To get a better understanding of the mechanics of this, click on the “research” on .  Read the material on the page called “Too much can make us sick.”  The material on the page “Toxic truth” might also be helpful.

Added sugar

Is there a connection between sugar consumption and gum disease?

The connection between sugar and gum disease has not been thoroughly investigated. However, a 2014 analysis of young adults participating in the most recent National Health and Nutrition Examination Survey found that frequent consumption of added sugars was associated with gum disease.[1] In addition, studies have shown that gum disease is associated with other chronic diseases such as heart disease and type 2 diabetes.[2,3,4,5] Gum disease may even be a predictor of these diseases.[4,6]

1. Lula EC, Ribeiro CC, Hugo FN, Alves CM, Silva AA (2014) Added sugars and periodontal disease in young adults: an analysis of NHANES III data. The American Journal of Clinical Nutrition 100: 1182-1187.

2. Scannapieco FA, Bush RB, Paju S (2003) Associations between periodontal disease and risk for atherosclerosis, cardiovascular disease, and stroke. A systematic review. Annals of Periodontology 8: 38-53.

3. Chávarry N, Vettore MV, Sansone C, Sheiham A (2009) The relationship between diabetes mellitus and destructive periodontal disease: a meta-analysis. Oral Health Prev Dent 7: 107-127.

4. Linden GJ, Lyons A, Scannapieco FA (2013) Periodontal systemic associations: review of the evidence. Journal of clinical periodontology 40: S8-S19.

5. Demmer RT, Jacobs DR, Desvarieux M (2008) Periodontal Disease and Incident Type 2 Diabetes: Results from the First National Health and Nutrition Examination Survey and its Epidemiologic Follow-Up Study. Diabetes Care 31: 1373-1379.

6. Xu F, Lu B (2011) Prospective association of periodontal disease with cardiovascular and all-cause mortality: NHANES III follow-up study. Atherosclerosis 218: 536-542.

Added sugar

If sugar & alcohol have the same mechanism in the liver which may lead to Metabolic Syndrome, can a person who doesn't drink eat more sugar?

The mechanisms behind metabolic syndrome are complex, but in terms of sugar limits, the guidelines are clear. Most of the recommended guidelines from health authorities, such as the ones we follow from the American Heart Association, are based on the total number of “discretionary calories” allowed based on your age, caloric needs and exercise level. They recommend limiting added sugar to no more than 50% of total discretionary calories (which includes sugar, saturated fat and alcohol). So, if you drink alcohol, you would have fewer discretionary calories to use for sugar and fat. Unfortunately, that means that if you don’t drink, you still need to keep below 6 teaspoons/9 teaspoons of added sugar per day. 


How much sugar is too much for ages 2-18?

The American Heart Association's (AHA) recommended limits for children vary depending on their age and caloric needs, but range between 3-6 teaspoons (12 - 25 grams) of added sugar per day. If the child is younger, aim toward a limit of 3 teaspoons (12 grams) per day. We reviewed a wide range of expert panel reports on dietary recommendations for added sugar, and found the AHA guidelines to be the best supported by the latest research on sugar and health. Our doctors recommend avoiding all added sugar for infants and toddlers.


Added sugarPackaged foods (processed)Table sugar

I have been off sugar for about a week and I have the most debilitating cravings. All I can think about is sugary treats. What can I do to lessen the cravings?

We have a couple of addiction research specialists on our team who are advocates of an evidence-based "relapse prevention approach" that focuses on: 1) removing the harmful substance from the environment (make it harder to obtain sugary foods and beverages - e.g., don't keep soda in the fridge and put sweet foods out of reach), 2) avoiding "cues" that trigger craving (avoiding situations and people that are associated with use of the substance) , and 3) promoting positive alternatives (making attractive alternatives easily within reach). And if those don't work, talk with your doctor about setting up a consultation with a nutritionist who might be able to help.

Added sugarTable sugar

Are foods like white rice, pasta and potatoes as unhealthy as added sugar?

About half of table sugar and high fructose corn syrup (on average) is glucose.  White carbs (like potatoes, white flour, etc.) are made of chains of glucose molecules.  White carbs are broken down in the body to glucose and are then stored as fat or burnt off during activity. Processing removes other nutrients and fibers in white carbs, which could speed up their digestion and absorption. While they don't have the fructose that has raised its own health concerns, the short answer is that sugars and starches are not much different, other than that your body takes the additional step of breaking the chains of glucoses down for absorption.

Added sugar

Do sugar alcohols also negatively impact the body?

Most of chemical names ending in "ose" are added sugars (e.g., sucrose or table sugar.)  Most chemical names ending in "ols" are sugar alcohols (e.g., Xylitol).  These are widely used in the food industry as thickeners and sweeteners.  They are less sweet than table sugar, sucrose, and are often combined with intensely sweet artificial sweeteners (e.g., stevia).  One advantage of sugar alcohols is that there is growing evidence that they don't contribute to tooth decay like sugars do. They do have calories, but generally fewer than table sugar and high fructose corn syrup.  They have a milder effect on blood glucose levels than sugar, making them a popular sweetener for diabetics.  But they can lead to stomach upset, bloating and diarrhea.  Our medical librarian, Evans Whitaker, did a review of the published literature on these sweeteners and could turn up very few studies examining their long-term health effects on metabolic health.  The simplest sugar alcohols, ethylene glycol and methanol, are sweet but notoriously toxic chemicals used in antifreeze. Also Xylitol is toxic to dogs, don’t let a pooch get ahold of your xylitol sweetened chewing gum! Please stay tuned to for news as we are monitoring this research.


I've heard that carrying extra weight around the waistline leads to increased cardiac risk. Is it the weight itself around the waist that makes you susceptible to cardiac risk, or is it the tendency to carry extra weight there that indicates a higher than average risk?

There is some evidence that the fats selectively deposited around the waist, for patients with Metabolic Syndrome, send off hormonal messages that further disrupt proper metabolic functioning.  So you are right to be concerned that carrying extra fat around the waist – as you put it, "the weight itself"– might be a risk factor for chronic diseases, such as heart disease.  But it's also true that the tendency to deposit visceral fat – what we call "sugar belly" – is one indicator of metabolic disease.  The best thing to do is to have your health care provider take some blood samples to evaluate your risk for Metabolic Syndrome, and follow his or her advice on addressing any concerns that arise.


Which is the greater risk for heart disease - salt or sugar?

This question has arisen a lot lately, in response to a recent study that found that processed sugars may contribute more to high blood pressure and heart disease than salt. One of our SugarScientists, Kirsten Bibbins-Domingo, MD, PhD, wrote a blog on this topic that gives a good overview of the issue. Her assessment is that we should not conclude that salt is suddenly good for you: it’s that sugar is worse than we thought.  Read her discussion here on why we need to avoid sugar AND salt for cardiovascular health.

Added sugarTable sugar

Does the 25 grams per day include the grams of carbohydrates that are not sugars but simple carbs?

No, we don't count them as "added sugar" in our recommended daily limits of 6 teaspoons (25 grams) for adult women and 9 teaspoons (38 grams) for men. Your statement about white carbs isn't completely true, but it is close. About half of table sugar and high fructose corn syrup (on average) is glucose. White carbs (like potatoes, white flour, etc.) are made of chains of glucose molecules. White carbs are broken down in the body to glucose and are then stored as fat or burnt off during activity. Processing removes other nutrients and fibers in white carbs, which could speed up their digestion and absorption.

So, in many ways, they are not much different. One significant difference, though, is that table sugar and corn syrup also contain fructose, which the science is increasingly linking to metabolic syndrome.

Added sugar

What is the metabolic difference between glucose, fructose, sucrose, and lactose? Which are most commonly over-consumed?

Table sugar (sucrose) and high-fructose corn syrup (HFCS) are the two most commonly consumed sugars in America and also the most over-consumed. Lactose is a sugar that naturally occurs in milk and is not counted as an added sugar in food. Both sucrose and HFCS are made up of about half glucose and half fructose, although HFCS can range from as low as 42% fructose to 65% or even higher. Fructose is unique from a metabolic standpoint, in that it is largely broken down in the liver. When the liver has to deal with large amounts of fructose, it processes the sugar into fat globules called triglycerides. Some of those fats are exported into the bloodstream, leading to metabolic diseases. Others are deposited in the liver, causing a condition known as non-alcoholic fatty liver disease. Fatty liver disease is a growing health concern for both adults and children.

Added sugarFructoseNatural Sugar (whole real foods)

Are artificial sweeteners a better choice than sugars?

The science is not yet clear on whether artificial sweeteners are better or worse than regular sugar. There is, however, emerging evidence that raises concerns. Artificial sweeteners can sometimes help people wean themselves off sugar. One question we’ve been concerned with for years involves the counterintuitive finding that consumption of artificial sweeteners is a predictor of overweight/obesity. New evidence published this year in the prestigious science journal, Nature, suggests one possible answer. In a series of studies in animals and humans the researchers found that a wide range of popular artificial sweeteners damage beneficial bacteria in the human digestive tract. This, they found, is linked to insulin resistance — a metabolic disturbance that occurs in people who consume too much added sugar. We will be watching this research carefully and will update as more studies on this topic are published.

FAQSubstitute sugars/ flavors/ preservatives

SugarScience Facts

Today, 31% of American adults and 13% of kids suffer from non-alcoholic fatty liver disease (NAFLD).

SugarScience Facts

Growing scientific evidence shows that too much added sugar, over time, is linked to diabetes, heart disease and liver disease.

SugarScience Facts

Too much fructose in added sugar can damage your liver just like too much alcohol.

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