A study by NCD Risk Factor Collaboration, a group of 800 or so scientists, in association with the World Health Organization (WHO) has stated that Dutch men and Latvian women are the tallest in the world among all the nationalities. The research titled 'A century of trends in adult human height' which was published in the journal eLife, has taken growth trends in 187 countries from 1914 to 2014. 

The average height of a Dutchman is nearly 183cm (6ft) tall while it is 170cm (5ft 7in) for a Latvian woman.

Source: b"A file photo of \xc2\xa0the world's shortest man, Chandra Bahadur Dangi, greeting the tallest living man, Sultan Kosen, to mark the Guinness World Records Day in London | Source: Reuters"

According to the study, the biggest growth trends has been witnessed in the European nations which have topped the rankings. However, the study doesn't show the Indian sub-continent on the bright side. In India, Pakistan and Bangladesh the increase in height has been recorded the lowest with 1-6cm in 100 years.

A BBC report states that the key factors are good standards of healthcare, sanitation, and nutrition. It also added that mother's health and nutrition during pregnancy also plays a crucial role. It adds that tall people tend to have a longer life expectancy, with a reduced risk of heart disease but also says that they are at greater risk of certain cancers, such as colorectal, postmenopausal breast and ovarian cancers.

Here's a video which tells what exactly makes Dutch the tallest:

The list of top 5 countries with the tallest men (1914 ranking in brackets):

1. Netherlands (12)

2. Belgium (33)

3. Estonia (4)

4. Latvia (13)

5. Denmark (9)

Source: b'A representational image | Source: AFP'

Here is the list of top 5 countries with the tallest women:

1. Latvia (28)

2. Netherlands (38)

3. Estonia (16)

4. Czech Republic (69)

5. Serbia (93)