The age-related decline in cardiorespiratory fitness is positively associated with incident Type 2 diabetes, say researchers, with the least fit individuals being at greatest risk for developing the condition over 20 years of follow-up.

The finding is reported by Mercedes Carnethon (Northwestern University, Chicago, Illinois, USA) and colleagues and was based on an analysis of participants in the Coronary Artery Risk Development in Young Adults study.

In this longitudinal study, 3989 Black and White men and women aged 15??”30 years were recruited in cities across the USA and re-examined multiple times over the next 20 years.

Writing in the journal Diabetes Care, Carnethon and team report that the rate of incident diabetes was 4 per 1000 person??”years in both men and women. The incidence of diabetes was higher among those who were less fit at baseline, say the researchers, and this was true for both men and women and Black and White individuals.

The average decline in fitness (defined as the difference in treadmill duration between baseline and 7-year follow-up) was 7.6% in women and 9.2% in men.

After adjusting for diabetes risk factors, each standard deviation decrease in fitness beyond the population average was associated with an increased likelihood for developing diabetes (hazard ratios 1.22 in women and 1.45 in men).

Interestingly, however, this association was largely accounted for by baseline body mass index.

Carnethon and team also examined the average decline in fitness over 20 years of follow-up, finding that the declines were significantly larger in those who developed diabetes than in those who did not (34.9% vs 27.0% in women and 37.9% vs 26.5% in men).

“Regular physical activity to improve and maintain cardiorespiratory fitness is an important component of a healthy lifestyle,” the authors conclude.

“By describing the association of changes in fitness over time with the long-term development of diabetes, we have identified one risk factor that, if modified, could lower the incidence of diabetes in the population.”

MedWire (www.medwire-news.md) is an independent clinical news service provided by Current Medicine Group, a part of Springer Science+Business Media. © Current Medicine Group Ltd; 2009

Free abstract

Adhering to a low-fat or low-carbohydrate diet for a year induces similar weight loss and has a similar effect on glycemic control for individuals with Type 2 diabetes, report researchers.

The team observed no effects of either diet on blood pressure, but the low-carbohydrate diet produced greater increases in high-density lipoprotein (HDL) cholesterol level than the low-fat diet.

Nichola Davis (Albert Einstein College of Medicine of Yeshiva University, Bronx, New York, USA) and colleagues recruited 105 overweight (mean body mass index 36 kg/m²) adults with Type 2 diabetes to take part in a 1-year dietary intervention study.

The participants were randomly assigned to a low-carbohydrate (n=55) or low-fat (n=50) diet.

The low-carbohydrate diet was based on the Atkins diet and started with a 2-week period of extreme carbohydrate restriction to 20??”25 g per day, followed by a gradual increase of around 5 g per week depending on weight loss. The low-fat diet was modeled on that used in the Diabetes Prevention Program, with a fat gram goal of 25% of energy requirement based on baseline weight.

Both groups received written guidance on the fat and carbohydrate content of foods and instructions on self-monitoring.

Davis and co-workers found that, although the low-carbohydrate group initially had a faster rate of weight loss, this was not maintained and at 1-year both groups had lost around 3.4% of their initial weight amounting to approximately 3 kg.

Of note, glycated hemoglobin (HbA1c) did not significantly improve in either group. The authors suggest this may be due to insufficient weight loss as previous studies have demonstrated that, on average, a 6-kg weight loss is required for a 0.55% reduction in HbA1c.

No significant alterations in blood pressure were seen in either group after a year; however, at 12 months, HDL cholesterol was increased by 0.16 mmol/l (6.19 mg/dl) versus an increase of 0.06 mmol/l (2.32 mg/dl) in the low-fat diet group.

“Our study demonstrates that among overweight patients with Type 2 diabetes, there was no significant difference in the weight or HbA1c change in participants after a low-carbohydrate compared with a low-fat diet for 12 months,” conclude the authors in the journal Diabetes Care.

MedWire (www.medwire-news.md) is an independent clinical news service provided by Current Medicine Group, a part of Springer Science+Business Media. © Current Medicine Group Ltd; 2009

Free abstract

A diagnosis of diabetes is a life-changing event for some people. Suddenly you are forced to pay close attention to your diet, monitor your blood sugar, and deal with other complications in your daily routine. Some diabetics who are struggling to control their blood glucose are turning to special dietary supplements for extra help. Are diabetic supplements worth the money?

Certain natural botanical extracts have been used for thousands of years to treat diabetes and related conditions. Scientific research continue to demonstrate that these substances can be very helpful for people with diabetes. The most beneficial are those that assist the body to use insulin better and to maintain a healthy blood sugar level.

Biotin, Vanadyl Sulfate, Bitter Melon Extract, Cayenne, Juniper, and Gymnema Sylvestre are only a few of the natural ingredients that enhance the body’s use of insulin. Each substance has slightly different properties, so they work best when taken in combination. For example, Vanadyl Sulfate seems to mimic insulin within the body, while Cayenne can help to reduce insulin resistance. Juniper, on the other hand, can help strengthen the pancreas, which is the organ that produces insulin.

Turning to blood glucose control, Chromium and Vitamin C are notable players. They both support glucose metabolism, which contributes to more stable glucose levels. Cinnamon Bark can assist in glucose tolerance. Huckleberry and Banaba Leaf Extract will also help stabilize or lower blood sugar.

Many supplements for diabetics contain nutrients that support general health. Ingredients that enhance enzyme activity, weight loss, and fat reduction are particularly important for persons with diabetes, who often need to lose some unwanted pounds.

Supplements have a cumulative effect and so it may take several months for you to notice an improvement in your health. It depends very much on your individual body chemistry and the severity of your diabetic condition.

How do you know if a supplement is working? You will want to chart your blood sugar readings as usual. When you find the supplement that is right for you, you can expect to see more normal blood sugar levels, weight or fat loss, more energy, and improved overall health. Some people find that their excessive hunger or their craving for sweets goes away.

In the best case scenario, correct supplementation can reduce your need for prescribed medication. Of course, no matter how good you feel, you should never change the way you take your medication without the approval of your physician.