Results after 4 weeks on a fast-food, high calorie diet.

The study reviewed here investigated the effects on insulin signaling in humans after consuming a fast-food, high calorie diet for 4 weeks that led to weight gain (Danielsson A., et al. 2009).

After we eat, insulin transports the glucose from the blood into the cells where it can be used for energy. People who develop type 2 diabetes first develop what is called insulin resistance, which means the insulin is no longer able to transfer the blood glucose into the cells as efficiently as it used to. This happens because receptors on the cells start to be less sensitive to the insulin signal.

The researchers conducting this study discovered that it did not take very long for the participants to develop insulin resistance. After only 4 weeks, they developed moderate systemic insulin resistance. The amount of insulin receptors was reduced similar to what happens in type 2 diabetes. These study participants gained 10% body weight, but they were still fairly lean with a body mass index of 24.3.

Even without being severely overweight these participants still developed insulin resistance.

Insulin resistance can not only lead to type 2 diabetes, but also many other serious diseases.

A high nutrient low glycemic index way of eating is how you can prevent insulin resistance and stay lean.

To read the original abstract, click on the reference below.



Reference:

Danielsson A, Fagerholm S, Ost A, Franck N, Kjolhede P, Nystrom FH, Strålfors P. Short-term overeating induces insulin resistance in fat cells in lean human subjects. Mol Med. 2009 Jul-Aug;15(7-8):228-34. Epub 2009 Apr 30.

Sitting time associated with cardiometabolic risk markers

Many people spend several hours daily watching television and in addition to that sit the major part of the day at work. The effects of both sitting time and TV viewing were investigated in 2,761 women and 2,103 men by measuring waist circumference, body mass index (BMI), resting blood pressure, triglycerides, HDL cholesterol, fasting and 2 hours postload plasma glucose and fasting insulin (Thorp, AA, et al. 2010., Dunstan DW, et al. 2010).

The results showed that sitting time for both men and women was detrimentally associated with waist circumference, BMI, systolic blood pressure, fasting triglycerides, HDL cholesterol, 2 hours postload plasma glucose and fasting insulin.

Most people could probably cut down on TV viewing, but spending hours exercising everyday would not be practical and possible. The good news is that it is not necessary to spend hours exercising everyday to improve these cardiometabolic risk factors.

If you have been reading prior blogs, you may remember research showing equal benefits of short, intensive interval training and much longer, but less intensive training. It showed that just some few minutes of the actual activity 3 times a week could save hours weekly, and it will still produce the same benefits. If you, in addition to that adjusted the way you eat to high nutrients, low glycemic index meals you would see a big difference in your health in just some few weeks.

To read the original abstracts, click on the references below.



References:

Dunstan DW, Barr EL, Healy GN, Salmon J, Shaw JE, Balkau B, Magliano DJ, Cameron AJ, Zimmet PZ, Owen N. Television viewing time and mortality: the Australian Diabetes, Obesity and Lifestyle Study (AusDiab). Circulation. 2010 Jan 26;121(3):384-91. Epub 2010 Jan 11.

Thorp AA, Healy GN, Owen N, Salmon J, Ball K, Shaw JE, Zimmet PZ, Dunstan DW. Deleterious associations of sitting time and television viewing time with cardiometabolic risk biomarkers: Australian Diabetes, Obesity and Lifestyle (AusDiab) study 2004-2005. Diabetes Care. 2010 Feb;33(2):327-34. Epub 2009 Nov 16.

Fish Oil improving marker of biological age.

Omega 3 fatty acids have been documented to provide numerous health benefits. The study referred to here investigated the effect of omega 3 fatty acids from fish oil on telomere length, a marker of biological aging (Farzaneh-Far R, et al. 2010).

Biological age is the physiological age (real age). Your biological age can be either more or less than your chronological age. A sixty year old person in good shape could for example have a biological age of only 50 years compared to a person that is not in shape who for example could have a biological age of 70 years.

In this study, telomere length was used as an indicator of biological aging. A telomere is a region of repetitive DNA at the end of a chromosome, protecting the chromosome from damage. The lengths of telomeres are linked to aging. A shortened telomere is associated with increased aging.

In this study, the lengths of telomeres were measured at the beginning of the study and after a 5 year follow up in patients with cardiovascular disease. Also measured were the levels of the omega 3 fatty acids EPA and DHA.

It was interesting that the individuals in the lowest quartile of EPA, DHA experienced the fastest rate of telomere shortening compared to those in the highest quartile of EPA, DHA.

According to this study, omega 3 fatty acids from fish oil lowered the biological age.

If you want to know more about the many benefits of omega 3 fatty acids, click here.

To read the original abstract, click on the reference below.



Reference:

Farzaneh-Far R, Lin J, Epel ES, Harris WS, Blackburn EH, Whooley MA. Association of marine omega-3 fatty acid levels with telomeric aging in patients with coronary heart disease. JAMA. 2010 Jan 20;303(3):250-7.

Mental stress associated with coronary artery calcification

We have all heard that excessive stress is unhealthy. The research referred to here investigated the association between cortisol response and a marker of subclinical coronary atherosclerosis (Hamer M., et al., 2009). Cortisol is a stress hormone.

The participants were exposed to mental stress through certain tasks. Coronary artery calcification was measured using electron beam computed tomography.

The participants who responded to the test with increased cortisol indicating increased stress was approximately 40%. That group also demonstrated a higher risk of significant coronary artery calcification.

How can we be more stress resistant? Exercise and meditation can both help us respond with less stress when exposed to stressful situations. The key is to do it regularly and incorporate these habits into your lifestyle.

To read the original abstract, click on the reference below.


Reference:

Mark Hamer, Katie O'Donnell, Avijit Lahiri, and Andrew Steptoe. Salivary cortisol responses to mental stress are associated with coronary artery calcification in healthy men and women. Eur. Heart J., Advance Access published on September 10, 2009; doi: doi:10.1093/eurheartj/ehp386.