The knowledge of foreign languages is useful not only in the professional plan, but also for health. It appears, studying of foreign languages makes brain more active and helps to protect it from ageing.
Scientists have found out that older persons’ (speaking foreign languages) brain works better, than brain of those who speak only their native language. Studying foreign languages is some kind of training for brain which helps to keep a lucidity of mind and ability to training in advanced age.
Thus, educational level of the person plays almost no role. The person can not have higher education, but know some languages, and thus his brain will work more actively, than for the person who has graduated from several universities.
Certainly, the knowledge of foreign languages is not an absolute protection against age changes occurring to brain, but nevertheless, it will help to prolong active years and keep a lucidity of mind.