Good news if you don’t like long work outs

We all know that exercise is a necessity if we are going to stay healthy. It needs to be part of a healthy lifestyle. Not everybody enjoys spending a lot of time in the gym however.

For those who would rather exercise for a short time when they do, the following study should be good news. The research was done on patients with diabetes, but you don’t have to be diabetic to benefit from this type of regime (Eriksen L, et al, 2007). These patients were randomly assigned to one of two exercise programs carried out at home on a bicycle. The training was done at 60% of maximal oxygen uptake, this was termed as moderate to high-intensity. One group did three 10-minute sessions per day while the other group did one 30-minute session per day. The program lasted for 5 weeks.

The cardiorespiratory fitness increased similarly in both groups, but there were additional benefits documented for the 10-minute 3 times daily group.

On an oral 3 hour glucose tolerance test fasting glucose, 120 minutes glucose and blood glucose concentration areas under the curve at 120 minutes and 180 minutes decreased in the 10-minute 3 times daily exercise group, but not in the 30-minute daily group.

For people who have blood sugar issues being insulin resistant or having type 2 diabetes, exercising in short intervals three times during the day definitely is the preference.

People who don’t have any blood sugar problems will not lose any benefits exercising in intervals during the day since the cardiorespiratory fitness increased similarly in both groups.

Reference:

Eriksen L, et al. Comparison of the effect of multiple short-duration with sing long-duration exercise sessions on glucose homeostasis in type 2 diabetes mellitus. Diabetologia. 2007 Nov;50(11):2245-53.

Low glycemic index foods reduce the risk for chronic disease.

The glycemic index is a way to rate how high a certain food will raise the blood sugar when compared to glucose or white bread. The higher the glycemic index of a food the higher it will raise the blood sugar.

Glycemic load is another way to rate food using both the glycemic index and the amount of carbohydrates in a serving.

There has been controversy for awhile over the effects of dietary glycemic index and glycemic load on the risk of chronic diseases and the important of eating low glycemic index, low glycemic load foods.

Researchers at the University of Sydney looked at studies with 4 to 20 years of follow up investigating if the glycemic index, load had any impact on chronic disease (Barclay AW, et al, 2008). They found a positive association between glycemic index and glycemic load for type 2 diabetes, coronary heart disease, gall bladder disease, breast cancer and also all disease combined.

The conclusion was that their findings support the hypothesis that higher blood sugar levels after eating is a universal mechanism for disease progression.

An example of a very low glycemic index meal would be a salad with beans which also is high in micro nutrients. This type of meal will stabilize your blood sugar and give you prolonged energy.

Reference:

Barclay AW, et al. Glycemic index, glycemic load, and chronic disease risk—a meta-analysis of observational studies. Am J Clin Nutr. 2008 Mar;87(3):627-37.

Feeling hungry? Just exercise.

Recent published research shows interesting connection between exercise and appetite (Broom DR, et al, 2008).

Two types of exercise regimes were evaluated for their effect on hunger and levels of the gut hormones acylated ghrelin and peptide YY. 90 minutes of weight training using free weights were compared with a 60 minute run as an aerobic exercise. A comparison was also made with the participants resting.

Changes in acylated ghrelin indicating suppressed hunger was seen with both the resistance training and the aerobic training while the peptide YY was only elevated after the aerobic training also indicating reduced hunger. The feeling of hunger was rated with both types of exercise and with rest.

This was only a small study, but interesting. The participants reported decreased hunger with both resistance training and aerobic exercise. If you are looking for appetite suppression, you may be better off with aerobic type exercise, but weight training should also help you feel less hungry.

Wishing you the best for the holidays. Now you know what to do to combat the urge to eat too much.

References:

Broom DR, et al. The influence of resistance and aerobic exercise on hunger, circulating levels of acylated ghrelin and peptide YY in healthy males. Am J Regul Physiol Integr Comp Physiol. 2008 Nov 5.

News headlines, vitamin C, E don’t protect against cancer

It has just been in the news that vitamin C and E did not protect against cancer, referring to an article appearing in the Journal of the American Medical Association (Gaziano JM, et al, 2008). The study included 14,691 participants including 1,307 men with a history of prior cancer when enrolled. 400 IU of vitamin E every other day and 500 mg of vitamin C daily was used. Researchers are quoted in the news saying that “large-scale, randomized trials” must still be conducted on the use of vitamin supplements and cancer, which is fine.

What is bad is that some of these news reports make it sound like nutritional supplements in general does not provide any benefits whatsoever.

Does this mean that nutritional supplements don’t provide any health benefits? To draw a conclusion like that would be to make a huge error since numerous studies have documented a variety of benefits from supplements.

There are many ways to design a research study. In general the more participants involved in a study the more reliable the study would be if the researchers have paid attention to important details. This does not mean that studies not having huge amount of participants would be invalid. If they are conducted properly they can give very valuable information. Most publish studies does not include 15,000 participants or more.

To call for more studies is good, but would you stop watching for cars before you cross a street just because you want more studies to prove that it would prevent injuries? I don’t think so because you believe there is enough existing evidence present even if there have been no large-scale studies conducted on the topic.

However, if you look at this a certain way there are a lot of reasons why it is pointless to watch for cars before you cross the street. There are of course times when there would be no cars coming, and even if one was coming the driver may be able to see you in time to stop, even if you did get hit, maybe you would not get hurt.

Still with all these maybe’s most sensible people would think it would be really irresponsible not to watch for cars when crossing a street.

Maybe we should ask these reporters to participate in a study on this topic. I suggest they should volunteer to be in the group that did not watch for cars when crossing.

Reference:

Gaziano JM, et al. Vitamins E and C in the prevention of Prostate and Total Cancer in Men: The Physicians’ Health Study II Randomized Controlled Trial. JAMA. 2008 Dec 9.

Fruit juice increases risk of diabetes

There are two types of diabetes, type I and type II. Type I diabetes is an autoimmune disease where not enough insulin is produced. While type I diabetes can occur in adult life it is much more common to be born with this condition. Since the pancreas of people with type I diabetes is not able to produce adequate insulin it has to be supplied as a medication.

Type II diabetes is also called adult onset diabetes because it usually occurs later in life, it often does not require the supply of insulin. People with this condition are still able to produce insulin even if they may not be producing as much as they used to. The problem with type II diabetes is what is called insulin resistance. Insulin resistance means that the receptors on the cells get less responsive (less sensitive) to the insulin. The insulin is for that reason not able to transfer the blood glucose (sugar) into the cells as effectively as it used to. Genetic factors can make somebody more susceptible to this problem, but high glycemic index foods and too little physical activity are major contributors to insulin resistance. High glycemic index foods are foods that are absorbed quickly and elevates the blood glucose high.

An interesting study involving 71, 346 female nurses aged 38-63 years of age was recently published. The researchers investigated the association between fruit, vegetable and fruit juice intake and the development of type 2 diabetes (Bazzano LA, et al, 2008).

Both increased fruit and vegetable consumption was documented to be associated with a lower risk for diabetes while the consumption of fruit juice was associated with an increased risk for diabetes.

This may not be that strange since fruit juice is quite sweet. It takes a lot of fruit to make a glass of juice, you would usually not be able to eat that much fruit at one time.

Reference:

Bazzano LA, et al. Intake of fruit, vegetables, and fruit juices and risk of diabetes in women. Diabetes Care. 2008 Jul;31(7):1311-7.

Strokes linked to increased nonfasting triglycerides

Nonfasting triglycerides mean the fat that is transported by your blood throughout the day.

It has been common practice for many years to test the fasting level of triglycerides together with cholesterol. It is less common however to test the triglyceride levels during the day when we have been eating because the triglycerides in the blood will be affected by what we eat. For that reason it would be difficult to compare one test to another unless we ate exactly the same food and had the blood drawn at the same time of the day. That of course is not practical so it is done by fasting. That does not mean that the triglycerides we transport in the blood during the day after we eat is not important. A recently published study showed us how important it is. This study involved 13,956 individuals and investigated the risk of ischemic stroke and the connection to nonfasting triglyceride levels (Freiberg JJ, et al, 2008).

The interesting results showed that as the nonfasting triglycerides went up, so did the risk for stroke.

Why would triglyceride levels be high during the day? Fat and sugar might be the culprit. Both insulin resistance and fatty foods can raise blood triglycerides. If you were to measure the triglyceride levels after eating french fries and a sweet milk shake you would be surprised how high it would be.

What can you do to decrease the blood triglyceride levels during the day? Cut down on high glycemic index foods, sweets and bad fats like saturated and trans fats, and don’t forget to exercise.

References:

Freiberg JJ, et al. Nonfasting triglycerides and risk of ischemic stroke in the general population. JAMA. 2008 Nov 12;300(18):2142-52.