A U.K. health watchdog said that children as young as five should be given lessons in sex and relationships, Sky News reported.

The National Institute for Health and Clinical Excellence (NICE) claim that good quality classes on sex, relationships and alcohol help youngsters understand the risks and consequences of their actions and resist peer pressure

Research shows that two-fifths of young people rate sex education in their school as poor or very poor, NICE said.

In draft guidance published Thursday, NICE said that sex and relationships education is "more effective if it is introduced before young people first have sex."

It calls for children to receive lessons which are "factually accurate, unbiased and non-judgmental," tailored to each age group, and take into account "cultural, faith and family" issues.

It means primary school pupils could start by learning about friendships and respecting others, the guidance said.

Plans for a new compulsory sex and relationships curriculum were contained in an education bill put forward by the U.K.'s Labour party under the last government, but dropped shortly after the general election was called following opposition from the Tories.

NICE's draft guidance says that pupils should receive sex education classes throughout their school careers — from primary school to early adulthood.

Simon Blake, chief executive of sexual health charity Brook, and part of NICE's program development group, said: "It's a myth that sex and relationships education encourages children to be more promiscuous or have sex at an early age.

Ministers are looking at sex and relationships education as part of a wider overhaul of the curriculum, the Department for Education said.

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