果汁と健康の関係
Hello everyone, welcome to SCIENSPOT. SCIENSPOT is a podcast that shines a spotlight on the latest
scientific technology from Japan. Your host is REN from SCIEN-TALK. Do you pay attention to
anything specific for your health? That is very important, isn't it? When it comes to juice,
especially fruit juice, you might often hear advice to limit it because of its high sugar content.
However, today on SCIENSPOT, I'm excited to share some surprising research findings from
University of Science Tokyo that might overturn that common belief. It turns out that moderate
consumption of fruit juice could potentially reduce the risk of type 2 diabetes for certain
individuals. Let's talk a little bit about type 2 diabetes, which is a key focus of this research.
Type 2 diabetes is a serious condition where blood sugar levels become too high either because the
hormone insulin doesn't work effectively or because not enough insulin is produced.
This condition affects over 500 million people worldwide and about 8% of adults in Japan.
It's understood that both genetic factors and lifestyle habits such as over-eating and
果汁と遺伝子の関連性
lack of exercise are complexity involved in its development. Previous studies on the link
between whole juice and type 2 diabetes have actually shown inconsistent results without
clear guidelines. For example, some reports suggested that drinking a lot of juice increases
the risk, while others did not. The research team behind this new study set out to resolve this
inconsistency. The research team utilized data from the JAMIC study, a large-scale collaborative
cohort study involving 13 universities and hospitals across Japan. This study incorporated
detailed health data and genetic information from 30,769 individuals. The most significant
aspect of this research is its use of a new indicator called the polygenic risk score or
PRS for short. What is PRS? Each of us has slightly different genes from birth. The researchers
analyzed about 920,000 genetic variations called SNPs that are related to type 2 diabetes.
They then quantified an individual's susceptibilities to diabetes based on these variations.
You can think of it as a genetic score for diabetes risk. The higher the PRS,
遺伝的リスクと果物ジュースの関係
the more genetically predisposed a person is to developing diabetes. The research team
categorized participants into five groups based on their PRS levels and focused on the top 20%
with the highest genetic risk. Now let's dive into the specific details of the study.
The research team thoroughly investigated the relationship between PRS, the frequency of whole
juice consumption, and the prevalence of type 2 diabetes. They also statistically adjusted for
other factors that could influence diabetes, such as age, sex, smoking habits, and exercise to
isolate the pure association. The results revealed a surprising fact. It was found the only among the
top 20% of individuals with a high genetic predisposition to diabetes, those who consumed
their fruit juice more frequently had a lower prevalence of type 2 diabetes. Specifically,
compared to those who rarely drank fruit juice, individuals who drank it less than once a week
had about a 20% lower prevalence of diabetes, and those who drank it once a week or more had
almost a 50% lower prevalence. Notably, drinking one to two cups per day showed the lowest values.
果汁の予防効果と個別化医療
This suggests that for individuals with high genetic risk, fruit juice may act as a preventive
shield against diabetes. On the other hand, in groups with low or medium genetic risk,
no clear association was found between fruit juice intake and diabetes. This indicates that
one size does not fit all. It's like a specific key that only opens a specific lock, the preventive
effect of fruit juice might only be effective for those with a keyhole of a genetic background that
matches. This research finding thoroughly highlighted the importance of personalized medicine and
precision nutrition. While juice has often been generally advised against due to its sugar content,
this study provides scientific evidence that for individuals with high genetic risk,
moderate consumption could actually be preventive. This is a highly significant outcome that could
lead to a variation of generalized nutritional guidelines and promote dietary recommendations
tailored to an individual's genetic makeup. Looking ahead, the researchers plan to use
follow-up data to verify whether fruit juice consumption actually reduces future diabetes onset.
果汁と遺伝子の相互作用
Furthermore, they aim to elucidate at a molecular level how components in fruit juice, such as
polyphenol, functionally interact with genes related to sugar metabolism. A future where
personalized dietary guidelines are formulated based on our individual genetic information might
be closer than we think. That's all for today's SciencePod. What did you think about the relationship
between genetic risk and fruit juice? This study shows us how science can redefine what we
previously considered common health knowledge. So SciencePod is broadcasted daily on weekday morning
in both Japanese and English. I'm releasing only this episode this week. Since it's a major
holiday week in Japan called Obon, I will resume releasing episodes next week. And I'd love for you
to listen to the podcast and post your notes and thoughts with the hashtag SciencePod.
Thank you for listening. See you next time.
