Caloric restriction mimetics, including some present in foods like spermidine, are also investigated for these or similar reasons. Such and similar dietary supplements may contribute to prevention or treatment, with candidate substances including apigenin, berberine, jiaogulan, and rhodiola rosea. Research funding Cancer research is funded by government grants, charitable foundations and pharmaceutical and biotechnology companies. In the early 2000s, most funding for cancer research came from taxpayers and charities, rather than from corporations. In the US, less than 30% of all cancer research was funded by commercial researchers such as pharmaceutical companies. Per capita, public spending on cancer research by taxpayers and charities in the US was five times as much in 2002–03 as public spending by taxpayers and charities in the 15 countries that were full members of the European Union. As a percentage of GDP, the non-commercial funding of cancer research in the US was four times the amount dedicated to cancer research in Europe. Half of Europe's non-commercial cancer research is funded by charitable organizations. The National Cancer Institute is the major funding institution in the United States. In the 2016 fiscal year, the NCI funded $5.2 billion in cancer research. Difficulties Difficulties inherent to cancer research are shared with many types of biomedical research. Cancer research processes have been criticised. These include, especially in the US, for the financial resources and positions required to conduct research. Other consequences of competition for research resources appear to be a substantial number of research publications whose results cannot be replicated. Replicability Public participation Distributed computing One can share computer time for distributed cancer research projects like Help Conquer Cancer. World Community Grid also had a project called Help Defeat Cancer. Other related projects include the Folding@home and Rosetta@home projects, which focus on groundbreaking protein folding and protein structure prediction research. Vodafone has also partnered with the Garvan Institute to create the DreamLab Project, which uses distributed computing via an app on cellphones to perform cancer research. Clinical trials Members of the public can also join clinical trials as healthy control subjects or for methods of cancer detection. There could be software and data-related procedures that increase participation in trials and make them faster and less expensive. One open source platform matches genomically profiled cancer patients to precision medicine drug trials. Dominance of cancer research Cancer research has grown considerably as indicated by the number of records that have been