Tea lowers anxiety, blood pressure

A new study supports earlier evidence that tea can not only reduce blood pressure but also calm anxiety, despite its caffeine content.

Japanese researchers tested two compounds found in tea – L-theanine, the amino acid contained in tea leaves, and caffeine – and their effect in the body when under stress.

They enlisted 14 subjects who underwent three separate trials, in which they took L-theanine and a placebo, caffeine and a placebo, or a placebo only, the Journal of Physiological Anthropology reports.

The subjects were then asked to complete mental activities under varying degrees of stress, such as solving arithmetic questions with their non-dominant hand submerged in a bucket of ice water.

Ai Yoto and her team from the University of Shizuoka found that L-theanine significantly inhibited the blood pressure increases in a high-response group, which consisted of subjects whose blood pressure rose more than average while performing a mental task after taking a placebo.

Caffeine also had an effect on blood pressure but to a lesser degree than L-theanine.

In addition, the L-theanine was shown to reduce tension-anxiety scores on mood tests.


Got a question about this story? Leave it in Comments & Questions below.

This article is tagged with the following keywords. Find out more about MyNBR Tags

Comments & Questions

Commenter icon key: Subscriber Verified

Post New comment or question

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.

NZ Market Snapshot

Forex

Sym Price Change
USD 0.7045 -0.0024 -0.34%
AUD 0.9439 0.0040 0.43%
EUR 0.6409 -0.0021 -0.33%
GBP 0.5367 -0.0008 -0.15%
HKD 5.4637 -0.0186 -0.34%
JPY 74.4600 0.3320 0.45%

Commods

Commodity Price Change Time
Gold Index 1320.8 5.240 2016-07-26T00:
Oil Brent 45.2 -0.060 2016-07-26T00:
Oil Nymex 42.9 -0.220 2016-07-26T00:
Silver Index 19.7 0.030 2016-07-26T00:

Indices

Symbol Open High Last %
NZX 50 7310.4 7324.6 7310.4 -0.12%
NASDAQ 5143.8 5146.9 5110.1 0.30%
DAX 10314.4 10352.3 10247.8 0.70%
DJI 18473.3 18542.4 18473.8 -0.12%
FTSE 6724.0 6780.1 6724.0 0.39%
HKSE 22193.3 22277.2 22129.7 0.40%
NI225 16526.1 16821.4 16383.0 1.72%
ASX 5537.5 5564.6 5537.5 0.04%