By 2050 the world may experience a demographic shift that will present challenges in many countries. The United Nations warns that the world needs to do more to adequately prepare for the increasingly ageing population.

The Ageing in the Twenty-first Century: A Celebration and a Challenge report found that by 2050 the population of people over-60 will be larger than the population of people under-15. By the next decade the elderly population will be over one billion and will increase by 200 million during the decade. The elderly population may reach two billion by 2050.

Both the United Nations Population Fund and the HelpAge, are concerned that countries, more specifically developing countries, will not adequately be prepared to provide healthcare, retirement, living arrangements and intergenerational relations.

"In many developing countries with large populations of young people, the challenge is that governments have not put policies and practices in place to support their current older populations or made enough preparations for 2050," the agencies said in a joint statement.

According to the report, by 2050, approximately 80 percent of the world's elderly population will be in developing countries. Currently, around 66 percent of the elderly population resides in developing countries.

At the report's launch in Tokyo, UNFPA Executive Director, Dr. Babatunde Osotimehin, said, "People everywhere must age with dignity and security, enjoying life through the full realization of all human rights and fundamental freedoms."

Following the report' launch, there will be a day of global activism where more than 60,000 seniors 60 and older will campaign as part of the Age Demands Action (ADA). ADA is grassroots campaign to fight age discrimination and combat the increasingly ageing population.

Today is the kick off for the campaign activities, as well as UN International Day of Older People. Throughout the day countries all over the world will participate in marches to ensure their voices are heard. They'll lobby their governments on imperative issues that affect the elderly population such as pension, healthcare, housing or access to work.

If you want to get involved in the grassroots campaign you can start by signing the ADA global petition. For more information visit helpage.org.