KEEPING INDOOR TEMPS LOWER INCREASES METABOLISM-BOOSTING BROWN FAT

A new small study has found that keeping indoor temperatures lower increases adults’ levels of healthy brown fat.  Brown fat is a specialized type of fat that is very metabolically active and helps to generate body heat.  Brown fat is plentiful in babies but adults have very small amounts.  Prior research has found that persons with greater levels of brown fat are less prone to developing obesity and diabetes.  This small study is one of the first to show that adults are capable of growing additional brown fat and that cooler indoor temperatures stimulate its growth while warmer temperatures cause the loss of this beneficial type of fat.

In this study, 5 healthy men lived in a temperature-controlled environment.  During the day they lived their normal lives but at the end of the day they returned for at least 10 hours to the climate controlled environment.  Temperatures were kept at 75°F during the first month, 66°F during the second month, and then back to 75°F during the third month, and finally up to 80.5°F during the fourth month. Researchers assessed brown fat levels using CT scans, as well as muscle and fat tissue biopsies.   They found that brown fat levels rose by 30-40% during the cool second  month, returned to original levels in the third month, and then fell below original levels in the warmer fourth month. 

Another important result was that participants’ insulin sensitivity (the amount of insulin the pancreas needs to produce to bring blood sugar levels down after a meal) improved as amounts of brown fat increased.  This is a key result because as the body’s cells become insensitive to insulin, diabetes develops.

What to do:  Research in the US indicates that over the last couple decades, target indoor temperatures have risen approximately 6°F.  While this was only a small study, consider keeping indoor spaces cooler. So, to give your metabolism a little boost, turn down the heat and turn up the air conditioner!

Articles adapted from:

http://consumer.healthday.com/diabetes-information-10/misc-diabetes-news-181/cooler-indoor-temps-may-help-good-fat-grow-689073.html

http://diabetes.diabetesjournals.org/content/early/2014/06/18/db14-0513.abstract?sid=a1948b2f-f658-48a3-abb8-5e0800df8451

http://www.sciencedaily.com/releases/2014/06/140622142228.htm

Source:

Lee P,Smith S, Linderman J, Courville AB, Brychta RJ, Dieckmann W, Werner CD, Chen KY, Celi FS.  Temperature-acclimated brown adipose tissue modulates insulin sensitivity in humans. Diabetes, June 22, 2014 DOI: 10.2337/db14-0513

EVEN WITHOUT WEIGHT GAIN, DIET HIGH IN SUGAR INCREASES BLOOD PRESSURE AND CHOLESTEROL

A recent review of existing studies on sugar consumption and heart health finds that regular consumption of too much sugar and other added sweeteners increases the risk of high blood pressure and elevated blood cholesterol, even when individuals maintain a healthy weight. 

These findings corroborate results released earlier this year that were based on data collected from the National Health and Nutrition Examination Survey (NHANES) which tracks over 31,000 Americans.  For this current review, researchers pooled the results of  all international studies done comparing the effects of higher versus lower added sugar consumption on blood pressure and lipids.  They found 37 trials reporting effects on lipids and 12 reporting effects on blood pressure.

The review concluded that as long as caloric and carbohydrate intake were kept the same, consuming a higher  percentage of calories from sugar did not contribute to more added weight.  But, eating a higher percentage of calories from sugar did result in significantly higher blood pressure levels and cholesterol levels.    So, even when consuming a sugary diet does not result in weight gain, it does increase one's risk of heart disease. 

What to do:  Avoid added sugar as much as possible.  Even at a healthy weight, a daily 20-oz serving of soda alone puts you over the limit of sugar intake.  Beware not only of foods we typically think of as sweets.  "Healthy foods" such as granola bars, cereal, sauces, canned & dried fruit, and yogurt contain substantial amounts of added sweeteners.  

Source:

L. A. Te Morenga, A. J. Howatson, R. M. Jones, J. Mann. Dietary sugars and cardiometabolic risk: systematic review and meta-analyses of randomized controlled trials of the effects on blood pressure and lipids. American Journal of Clinical Nutrition, 2014; DOI: 10.3945/ajcn.113.081521

Articles adapted from:

http://www.nzherald.co.nz/lifestyle/news/article.cfm?c_id=6&objectid=11256097 

http://www.sciencedaily.com/releases/2014/05/140515095633.htm