Low HDL cholesterol associated with poor memory

HDL cholesterol is the good cholesterol which protects against harmful buildup in the arteries. It is considered good to have high HDL since it can provide some protection against cardiovascular disease.

It is interesting that low levels of HDL have now been found to also be associated with poor memory (Sigh-Manoux A, et al, 2008.) The study referred to here included 3673 male and female participants with an average age between 55-61 years. When the memory was evaluated, it was documented that a decrease in HDL over the five year follow up period was associated with a decline in memory.

This is another good reason for keeping your HDL level high. You can increase your HDL cholesterol by incorporating low glycemic index meals, avoiding trans fat and including omega 3, fat like fish oil in your diet, and also by exercising regularly.

Singh-Manoux A, et al. Low HDL cholesterol is a risk factor for deficit and decline in memory in midlife: the Whitehall II study. Arterioscler Thromb Vasc Biol. 2008 Aug;28(8):1556-62. Epub 2008 Jun 30.

Optimal vitamin D level may help you lose more body fat

Vitamin D has been found to be important for numerous reasons. In a recent study it was also documented that women who had a higher blood level of 25 hydroxyvitamin D lost more body fat when compared with women with a lower 25 hydroxyvitamin D level (Ortega RM, et al, 2008). 25 hydroxyvitamin D is the preferred test for vitamin D status.

The study included overweight/obese women between the age of 20-35 years of age. The women were put on slightly caloric restricted diets which led to a reduction in body weight and body mass index in both the women with lower and higher vitamin D levels. What made this study interesting was that women with hydroxyvitamin D levels of 50 nmol/L or more lost more body fat than the women who had hydroxyvitamin D levels of less than 50 nmol/L.

We get vitamin D from sunshine, but because of less exposure and protection from sunscreens, most people need to supplement with vitamin D to reach optimal levels. Vitamin D3 is the recommended form to take.

References:

Ortega RM, et al, 2008. Preliminary data about the influence of vitamin D status on the loss of body fat in young overweight/obese women following two types of hypocaloric diet. Br J Nutr. 2008 Aug; 100(2):269-72

Eating irregularly is a risk factor for the metabolic syndrome and insulin resistance.

The metabolic syndrome is a condition consisting of multiple symptoms including elevated blood glucose, triglycerides, cholesterol, LDL (the bad cholesterol) and decreased HDL (the good cholesterol). A part of the metabolic syndrome is insulin resistance which occurs when the insulin is not able to transfer the bloodsugar into the cells as efficiently as it used to. This will first result in elevated insulin levels as the pancreas compensates trying to transfer the glucose into the cells so it can be used for energy. Later the blood glucose may also increase as the pancreas is not able to compensate and the insulin resistance get worse. Symptoms are usually weight gain especially around the waist, less energy and increased low grade inflammation.

Risk factors associated both insulin resistance and the metabolic syndrome are not enough physical activity, stress and high glycemic index foods. Skipping meals can also be added to the list of risk factors, this was documented in a Swedish study recently (Sierra-Johnson J, et al, 2008). This makes sense since going a long time without eating results in glucose production in the liver to avoid low blood sugar. With time, the liver may produce more glucose than needed which will result in increased blood sugar.

Triggering this response is the hormone glucagone which stimulates the body to break down its own protein. The protein (amino acids) are then converted to glucose in the liver. This is a quicker way to produce energy than using fat which the body also will do.

The results is usually weight gain especially around the waist, the break down of muscle tissue because that is a big source of protein, and lack of energy.

The best way to ensure that you have high energy and stay lean is to eat high nutrient, low glycemic index foods regularly and not skip meals. Many smaller meals are better than 1 or 2 big meals. Exercise should of course also be a part of your routine.

References:

Sierra-Johnson J, et al, 2008. Eating meals irregularly: a novel environmental risk factor for the metabolic syndrome. Obesity (Silver Spring). 2008 Jun;16(6): 1302-7.

Losing fat may slow your thyroid.

It has been a belief for a long time that starving yourself would slow down the thyroid and not be productive in the long run if you want to lose weight, especially if you want to lose fat.

This was now confirmed in a recent study where the participants were randomly assigned to either a caloric restriction group, an exercise induced weight loss group, or a placebo group for 12 months (Weiss EP, et al, 2008).

The fat mass decreased significantly in both the caloric restricted group and the exercise group, but not in the placebo group. There were not a significant difference in fat loss between the caloric restriction group and the exercise group. What was interesting however was that the plasma concentration of the thyroid hormone T3 decreased in the caloric restricted group, but not in the exercise group even if both of the groups lost about the same amount of fat.

The lesson is that if you want to lose weight and stay healthy, exercise should be a part of the program in addition to a healthy diet.

References:

Weiss EP, et al. Caloric restriction but not exercise-induced reductions in fat mass decrease plasma triodothyronine concentrations: a randomized controlled trial. Rejuvenation Res. 2008 Jun;11(3):605-9.

Common drug linked to increased risk of asthma and eczema in children.

If you have children the results of a new study just published should be of interest to you.

This was a large study that included 205,487 children aged 6-7 years old from 73 centers in 31 countries (Beasley R, et al, 2008). The researchers investigated the association between the use of paracetamol which is acetaminophen and asthma. Acetaminophen is sold under the brand name Tylenol which you probably are more familiar with.

The result showed that the use of paracetamol in the first year of life and in children aged 6-7 years was associated with the risk of severe asthma symptoms and also with an increased risk of symptoms of rhinoconjunctivitis (inflammation of the eyes) and eczema.

You may want to think twice before you give your child a medication to reduce fever and pain. In most cases it would probably not be necessary and the child could be better off without it.

References:

Beasley R, et al. Association between paracetamol use in infancy and childhood, and risk of asthma, rhinoconjunctivitis, and eczema in children aged 6-7 years: analysis from Phase Three of the ISAAC programme. Lancet. 2008 Sep 20;372(9643):1039-48.