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Obesity in grizzlies, a natural adaptation to hibernation. 
Researchers writing in Cell Metabolism report that as grizzly bears become obese in preparation for winter and hibernation, they respond normally to insulin – which prevents the breakdown of fatty tissue. But during hibernation, their insulin effectively stops working. This insulin resistance allows the bears to break down their fat stores throughout hibernation (they don’t eat, drink or defecate for up to seven months). They survive on their fat. When they wake up and start eating again, they respond normally to insulin.

Grizzly bear
Pic: Kevin Corbit

The insulin levels in their blood do not change. The cells that insulin communicates with turn on and off their ability to respond to insulin. When the bears are most obese, they are also the most insulin sensitive, and they become this way by shutting down the activity of a protein called PTEN in their fat cells. “This is in contrast to the common notion that obesity leads to diabetes in humans,” says Dr. Kevin Corbit, of Amgen, Inc. The researchers also found that grizzlies somehow store all of the fuel they need during hibernation in fat tissue, not in liver and muscle, which are common places for fat to accumulate in other animals with obesity.  

Chew on this. 
People with diabetes are at greater risk of developing gum disease (gingivitis and periodontal disease) than people who do not have diabetes. Gum disease is a bacterial infection in the mouth can cause blood glucose levels to rise. The link is inflammation. The build-up of inflammatory substances in the blood can worsen chronic health conditions.

A recent study that involved checking the health and dental insurance records of 338,891 people with one of five conditions (type 2 diabetes, heart disease, cerebrovascular disease, rheumatoid arthritis and pregnancy), found that periodontal therapy can improve health. The researchers report that within 4 years, people who had treatment for gum disease had lower medical costs and fewer hospitalisations compared with people who didn’t have treatment. For example, people with cardiovascular disease and diabetes who had the gum disease treatment had health-care costs that were between 20% and 40% lower.

Gum disease is usually caused by a build-up of plaque on teeth. One of the common signs is bleeding gums. Tips for maintaining healthy teeth and gums include:

  • Brushing twice a day with a soft, small-headed toothbrush. 
  • Carefully flossing each day. 
  • Visiting your dentist every six months for a check up and clean. 
  • Eating a healthy diet including plenty of low GI whole grains. 
  • Managing your blood glucose levels if you have diabetes. 
  • Quitting smoking if you do – people who smoke are 4 times more likely to develop gum disease than people who don’t.

Healthy teeth

Sugars, sweeteners and tooth decay. 
This is an edited extract from the Ultimate Guide to Sugars and Sweeteners  reproduced courtesy The Experiment Publishing (New York). 

Sugars and starches (highly fermentable carbohydrates) can all contribute to tooth decay, but overall, with the exception of lactose, sugars appear to be more likely to promote tooth decay (be cariogenic) than starches. Whether or not a sugary food or drink will cause tooth decay depends on:

  • How much and how often you consume the food or drink 
  • The food’s acidity and its buffering power (that’s the food’s ability to minimize the overall acidity) 
  • The food’s consistency (texture) and its retention in your mouth 
  • Your overall eating and drinking pattern (i.e., how much and how often you eat and drink). 

Your susceptibility to developing tooth decay also depends on your mouth bacteria, the flow rate and composition of your saliva, and whether or not you live in an area that has a fluoridated water supply and/or use fluoride toothpaste.

Consuming added sugars and foods high in added sugars frequently, is clearly associated with an increased risk of developing dental caries, independent of the actual amount you eat or drink. Rather than nibble or sip on them throughout the day, you are probably better off downing them in a single sitting and then brush your teeth with fluoride toothpaste.

Polyols (sugar alcohols) are not well fermented by oral bacteria, nor do they have the acidifying impact on plaque that most sugars do and they generally do not promote tooth decay. Some studies have even suggested that xylitol may be anti-cariogenic, as it has antibacterial properties that act on some of the fermenting bacteria found in plaque.

Nonnutritive sweeteners (NNS) from aspartame to stevia are also not well fermented by oral bacteria, nor do they have the acidifying impact on plaque that most sugars do. So, generally they do not promote tooth decay. However, it comes down to how they are used. For example, “diet” soft drinks that contain NNS are acidic, which means they can still, in theory, contribute to dental erosion. In addition, because they are usually so sweet, most NNS are diluted and bulked up for tabletop use. The bulking agent is frequently maltodextrins, which can be used as a fuel by oral bacteria. So, in theory, some nonnutritive tabletop sweeteners may contribute to tooth decay.