Drinking tomato juice daily for five weeks after avigorous
workout or physical activity in untrained individuals can reduce ROS-induced
oxidative stress, according to a Swedish study published in the Nutrition
Journal.
Reactive oxygen species (ROS) that include oxygen ions,
hydroxyl ions and peroxides play an important role in the development of cancer
and aging process. They react with cellcomponents such as proteins, lipids, and
DNA and bring about chemical modifications in the cells, causing what is known
as oxidative stress.
Under normal
conditions,anti-oxidants present in the cell fight ROS and bring down their
levels thereby minimizing damage to the cells. Regular physical activity or
exerciseand diet rich in antioxidants, thus, protect against oxidative
stress,especially DNA based damage.
Oxidative stress
induced DNAdamage is measured by the concentration of 8-Oxo-2'-deoxyguanosine
(8-oxo-dG)present within the cell.
So, to investigate
whether tomato juice protects againstROS induced by extensive physical exercise
in untrained individuals, Swedishresearchers Mats Harms-Ringdahl and colleagues
from Centre for RadiationProtection Research (CRPR), Department of Genetics,
Microbiology andToxicology, Stockholm University, Sweden, used 8-oxodG as
'sensitive marker' of oxidative stress.
They monitored
serumlevels of 8-oxodG using a modified ELISA. Fifteen untrained
healthysubjects were given 150 ml tomato juice per day for two 5- week periods
with a5- week-without- tomato-juice period in between the two periods. Blood
sampleswere taken before and after each period. At the day of blood collection,
thesubjects performed a 20-minute acute physical exercise using an
ergometerbicycle.
The results showed
that -
. Blood serum 8-oxodG increased significantly in allsubjects
after an acute physical exercise. This suggests a positive correlationbetween
8-oxodG in serum and ROS production.
. Tomato juice intake (15 mg lycopene) of150 ml per day
significantly protected the nucleotide pool of the DNA from ROSproduced in
response to extensive physical activity.
Besides lycopene,
tomatoes also contain vitamin C,tocopherols and polyphenols but lycopene is
found to be the most abundant andstable in food processing. Therefore, the
researchers believed that lycopene isresponsible for the antioxidant activity
in tomato juice.
They concluded -
'Long term intake of tomato juice mayreduce oxidative stress levels in patients
with enhanced level of oxidativestress, for example, patients with diabetes,
cardiovascular diseases orinflammation'.
Reference: Harms-Ringdahl M, Jenssen D, Haghdoost S. Tomatojuice intake suppressed serum concentration of 8-oxodG after extensive physicalactivity. Nutr J. 2012 May 2;11(1):29. http:www.nutritionj.com/content/pdf/1475-2891-11-29.pdf