That paradox has been captured by a new global report that ranks Tanzania ahead of the other East African countries in the overall assessment of happiness.
The report, under the The Legatum Prosperity Index for 2011 banner, describes happiness as a measurement of both wealth and wellbeing, for which Tanzania was placed at position 96 out of the 110 surveyed countries.
The country emerged tops in the East African Community (EAC) bloc, trailed by Rwanda (98), Uganda (100) and Kenya (102). Burundi was not ranked due to lack of relevant data.
But Tanzania's neighbours fair better on aspects described as satisfaction with life and optimism for the future.
Its people have furthermore been judged to be the most vulnerable in nursing worries.
On the satisfaction yardstick, Tanzania scored 3.2 in a scale of 10. Kenyans who were lumped among the last 10 countries in happiness, still had the most optimistic people in EAC, with an average life satisfaction score of 4.3, followed closely by Uganda with 4.2 and Rwanda 4.0.
The index defines prosperity as both wealth and wellbeing, and finds that the most prosperous nations in the world are not necessarily those that have only a high Gross Domestic Product (GDP), but are those that also have happy, healthy, and free citizens.
The London-based organisation studies eight sub-indexes, each of which represents a fundamental aspect of prosperity which focuses on the economy, entrepreneurship and opportunity, governance and education.
Others are safety and security, personal freedom and social capital.
Experts in human behaviour and economics as well as independent commentators, say several reasons could explain why Tanzanians appear the least optimistic in life even though their nation is shown as being averagely happiest.