17/09/2014 13:59 BST | Updated 17/11/2014 05:59 GMT

Mid-Life Health Affects Your Risk of Dementia

A staggering fact: if a person dies at 80 with Alzheimer's, the disease may have started in their brain at age 45.

Fascinating and frightening as this fact may be, it shows that there's no stronger incentive than to improve your health as you move through the middle years of your life. The World Alzheimer Report published today by Alzheimer's Disease International, tells us that dementia isn't something that suddenly affects you when you're in your later years. The time is now, today, right this second, for making changes to protect your memories and brain health.

We know that over two-thirds of people Bupa surveyed around the world are worried about getting dementia, but many don't realise what they can do to help prevent it.

One of the key messages for me and a good motto to adopt is 'what's good for your heart is good for your brain.' The report demonstrates this in a number of ways.

When you think of smoking, it's likely you may think of lung cancer as an immediate association. And you'd be right, but it's also a risk factor for dementia. Tobacco smoke contains hundreds of toxic chemicals which can affect your brain; it also contributes to the risk of stroke which in turn increases the risk of vascular dementia.

The report found that people who quit smoking had the same risk of developing Alzheimer's as non-smokers. Whereas smokers have a higher risk of Alzheimer's compared to never smokers. Smokers have a 45% higher risk of developing dementia than non-smokers. It's my firm belief that quitting smoking is one of the most important things you can do to improve and safeguard your health: against cancer, heart disease, diabetes and now, dementia.

It's not all about what you should stop doing. It's also about what you should start doing and keep doing - like being physically active.

The brain benefits of being physically active are twofold: one, exercising reduces the risk of non-communicable diseases (NCDs) like obesity, cardiovascular disease (CVD) and diabetes, all of which increase the risk of dementia. And secondly, there's a suggestion that physical activity can benefit the inner workings, structure and function of our brain. There isn't enough evidence at the moment to specifically recommend physical activity as a way to reduce or prevent dementia and cognitive decline - more research is needed. But, we can be confident that its role in preventing NCDs is indirectly related to preventing dementia.

Going back to that motto - what's good for your heart is good for your brain - it certainly rings true when it comes to preventing, detecting and taking control of conditions like high blood pressure and diabetes.

There's strong evidence that having high blood pressure (hypertension) in mid-life is associated with developing dementia in later life. Therefore, if you've not had your blood pressure checked recently, now's a good time to see your doctor. Prevention and early treatment of high blood pressure will not only protect your heart, it may protect your brain too.

And, having type 2 diabetes in later life (and probably in mid life) is linked to an increased risk of dementia, particularly vascular dementia. In fact, diabetes can increase the risk of dementia by 50%. Type 2 diabetes is largely preventable because it's usually caused by unhealthy habits like a poor diet, being overweight, smoking and not exercising. All things you can change.

The takeaway messages from this report clearly show that making changes in mid-life is fundamental to minimising the risk of dementia in later life. Yet it's equally important to emphasise that it's never too late to make a change. Even in later life, adopting a healthier lifestyle is a positive step to reducing the world's largest health burdens of dementia, cancer, CVD and diabetes. Furthermore, even people who have dementia, or signs of it, should also adopt healthy habits because they may help slow the progression of the disease.

The findings of this report come at a critical time. The number of people currently living with dementia across the world is around 44 million. That figure is set to double by 2030 and triple by 2050. It's time to take action. There's a strong call for dementia to be integrated into both global and national public health programmes alongside other major NCDs. In 2010, the global cost of dementia care was estimated at US$604 billion. Based on current estimates, this figure is expected to rise to US$1 trillion by 2030. With this in mind, we can't afford to do nothing.

To quote the report: "If we can all enter old age with better developed, healthier brains we are likely to live longer, happier and more independent lives with a much reduced chance of developing dementia." It's clear to me that dementia can't be pushed to the back of our minds as something to worry about in later life. Out of sight, out of mind just isn't a viable option. The findings of this report say to me that there's no time like the present.