Most of us want to feel and look better. We know we should eat healthy food, walk more, exercise more, and in general, follow a healthy lifestyle to achieve that. But it's easier said than done. It seems that sometimes, where there is a will, there is no way. Fed with good intentions, we think we will do it one day, but somehow that day is not arriving. We simply cannot make it happen despite all the wishful thinking and projecting. Why can't we make it happen? The reality is we feel too tired to start. According to a new survey from YouGov, tiredness is the biggest barrier for people to implement changes in their lifestyle. Brits are simply feeling too tired. The results are based on a poll of 2,086 UK adults for the World Cancer Research Fund (WCRF). In the poll, 35% of respondents claimed that tiredness is the reason why of they don't make changes to their diet and physical activity levels. When asked what was stopping them from eating more healthily and exercising more often, 29% of men and 40% of women cited "feeling too tired" Matt Lambert, the WCRF's health information and promotion manager, said: "People have busy schedules and we know that, for many, the last thing they might want to do when they are tired or lacking in motivation is to start cooking from scratch or going to the gym." Following a healthy lifestyle that includes exercise are important ways of reducing the risk of getting many diseases, including cancer. WCRF and Cancer Research UK, estimate that 40% of cancer cases could be avoided if more people lived healthier and more conscious lives. This could be achieved by eating more healthy food, being more active, giving up smoking, maintaining a normal weight and avoiding sunburn. The charity is launching a healthy living plan to help people build healthier food and activity habits into their routine.