Beetroot Juice – Recent Study

Many thanks to my client that asked me about beetroot juice and cycling.  If you are a keen cyclist check with your Sports Dietitian before filling your drink bottle with beetroot juice!  It may not meet all your fluid and performance goals.   In June this year, the Journal Med Sci Sports and Exercise published an article on beetroot juice and cycling time trial performance.  It was a preliminary study as it only had 9 athletes in the trial.  It was a randomised trial meaning that for one experiment athletes were given 500mls of beetroot juice and for the next trial 500mls of nitrate-depleted beetroot juice.  The study did show an improvement in cycling performance for a 4km and 16.1km cycling time trials of 2.8% and 2.7%.  The big question now is will the results be the same when a larger group of athletes try the same experiment?  Are there any side effects of drinking 500mls of beetroot juice just before a cycling time trial?  Love to hear any experiences if you have tried this already.

Does the seed extract from African Mango speed up weight loss?

It’s spring and people start thinking about trying to lose weight.  It’s also human to want to lose weight fast (even though logic tells us that you can only burn 1kg of fat fairly slowly).  I saw a claim about African Mango seed extract in the paper saying that it got results such as 5.5kg weight loss in 30 days.

Does it work?  Short answer to the question is maybe it can help with weight loss.  There have been two small human studies that look promising.  However, the longest study was for 10 weeks (not long) and only 102 people were in the study, long term weight loss results and side effects are unknown. 

Details:  In the ten week study, half the volunteers (51 people) were on the ‘pretend’ (placebo) extract and the other half (51 people) took active dose of the Irvingia gabonensis seed extract (150mg) before both lunch and dinner.  Eighteen people dropped out which could effect the results.  Side effects were reported as headache (5 people), sleep difficulty (6 people), and intestinal flatulence/wind (6 people).  After 10 weeks of the study, there were promising drops in body weight (eg 12.5kgs), body fat, waist measurements and cholesterol.  However, the next type of study needed to back up these preliminary results would need to include a larger number of people (say 1500), the study would need to run for 1 to 2 years to look at long term weight loss results and any potential side effects and the study would need to try to prevent people from dropping out.

Bottom line:  Further studies are needed to get a better idea if this extract can help with weight loss without any serious side effects.  If you see a weight loss product that includes this extract does it have the kind of dosages used in the study (eg 150mg twice a day)?  Can you afford to buy it knowing that it may or may not help with weight loss?  Does the supplement have any other herbs that may interact with other medications or sleep (eg guarana is a herb that contains caffeine)?  Discuss with you Doctor seeing as the long term side effects are unknown.

Brown and White rice and Diabetes Risk

Recent Study looking at Brown or White Rice and Diabetes Risk

I’ve had lots of questions and comments about this one and the study was only published on June 14!

If you already have diabetes, this study does not apply.  If you eat rice and already have diabetes the main things to think about are portion size (think small), low glycaemic index (basmati or doongarra rice) and health benefits (brown rice has more fibre and B vitamins).

This study was looking at people without diabetes and whether their rice eating pattern raised or lowered their risk of getting type 2 diabetes.  (White rice, brown rice and the risk of type 2 diabetes in US men and women.  Archives Internal Medicine 2010 June 14 170 (11) 961-969.

The study looked at the long term eating patterns of health professionals in America (39 765 men and 157 463 women).  The key findings were:

– Eating five or more serves of rice per week gives a 17% higher risk of developing type 2 diabetes then people that ate less than 1 serve of white rice per month.
– Eating brown rice, two or more times a week, reduces the risk of developing type 2 diabetes by 11%.  This was compared to people that ate brown rice less than once a month.

So if you don’t have diabetes and want to reduce your risk of developing diabetes, as you get older, brown rice rather than white rice would be a healthy option.  

Cooking tips – brown rice takes longer to cook so plan ahead and get the rice cooking first before preparing a stir fry.  Brown rice has a nutty texture which takes a while to get used to but very enjoyable.