Vitamin D is essential for bone health, immune function and overall wellbeing. And it becomes even more crucial as we age.

New guidelines from the international Endocrine Society recommend people aged 75 and over should consider taking vitamin D supplements.

But why is vitamin D so important for older adults? And how much should they take?

Young people get most vitamin D from the sun

In Australia, it is possible for most people under 75 to get enough vitamin D from the sun throughout the year. For those who live in the top half of Australia – and for all of us during summer – we only need to have skin exposed to the sun for a few minutes on most days.

The body can only produce a certain amount of vitamin D at a time. So staying in the sun any longer than needed is not going to help increase your vitamin D levels, while it will increase your risk of skin cancer.

But it’s difficult for people aged over 75 to get enough vitamin D from a few minutes of sunshine, so the Endocrine Society recommends people get 800 IU (international units) of vitamin D a day from food or supplements.

Why you need more as you age

This is higher than the recommendation for younger adults, reflecting the increased needs and reduced ability of older bodies to produce and absorb vitamin D.

Overall, older adults also tend to have less exposure to sunlight, which is the primary source of natural vitamin D production. Older adults may spend more time indoors and wear more clothing when outdoors.

As we age, our skin also becomes less efficient at synthesising vitamin D from sunlight.

The kidneys and the liver, which help convert vitamin D into its active form, also lose some of their efficiency with age. This makes it harder for the body to maintain adequate levels of the vitamin.

All of this combined means older adults need more vitamin D.

Deficiency is common in older adults

Despite their higher needs for vitamin D, people over 75 may not get enough of it.

Studies have shown one in five older adults in Australia have vitamin D deficiency.

In higher-latitude parts of the world, such as the United Kingdom, almost half don’t reach sufficient levels.

This increased risk of deficiency is partly due to lifestyle factors, such as spending less time outdoors and insufficient dietary intakes of vitamin D.

It’s difficult to get enough vitamin D from food alone. Oily fish, eggs and some mushrooms are good sources of vitamin D, but few other foods contain much of the vitamin. While foods can be fortified with the vitamin D (margarine, some milk and cereals), these may not be readily available or be consumed in sufficient amounts to make a difference.

In some countries such as the United States, most of the dietary vitamin D comes from fortified products. However, in Australia, dietary intakes of vitamin D are typically very low because only a few foods are fortified with it.

Why vitamin D is so important as we age

Vitamin D helps the body absorb calcium, which is essential for maintaining bone density and strength. As we age, our bones become more fragile, increasing the risk of fractures and conditions like osteoporosis.

Keeping bones healthy is crucial. Studies have shown older people hospitalised with hip fractures are 3.5 times more likely to die in the next 12 months compared to people who aren’t injured.

Vitamin D may also help lower the risk of respiratory infections, which can be more serious in this age group.

There is also emerging evidence for other potential benefits, including better brain health. However, this requires more research.

According to the society’s systematic review, which summarises evidence from randomised controlled trials of vitamin D supplementation in humans, there is moderate evidence to suggest vitamin D supplementation can lower the risk of premature death.

The society estimates supplements can prevent six deaths per 1,000 people. When considering the uncertainty in the available evidence, the actual number could range from as many as 11 fewer deaths to no benefit at all.

Should we get our vitamin D levels tested?

The Endocrine Society’s guidelines suggest routine blood tests to measure vitamin D levels are not necessary for most healthy people over 75.

There is no clear evidence that regular testing provides significant benefits, unless the person has a specific medical condition that affects vitamin D metabolism, such as kidney disease or certain bone disorders.

Routine testing can also be expensive and inconvenient.

In most cases, the recommended approach to over-75s is to consider a daily supplement, without the need for testing.

You can also try to boost your vitamin D by adding fortified foods to your diet, which might lower the dose you need from supplementation.

Even if you’re getting a few minutes of sunlight a day, a daily vitamin D is still recommended.

Elina Hypponen, Professor of Nutritional and Genetic Epidemiology, University of South Australia and Joshua Sutherland, PhD Candidate – Nutrition and Genetic Epidemiology, University of South Australia

This article is republished from The Conversation under a Creative Commons license. Read the original article.

“Childhood” and “dementia” are two words we wish we didn’t have to use together. But sadly, around 1,400 Australian children and young people live with currently untreatable childhood dementia.

Broadly speaking, childhood dementia is caused by any one of more than 100 rare genetic disorders. Although the causes differ from dementia acquired later in life, the progressive nature of the illness is the same.

Half of infants and children diagnosed with childhood dementia will not reach their tenth birthday, and most will die before turning 18.

Yet this devastating condition has lacked awareness, and importantly, the research attention needed to work towards treatments and a cure.

More about the causes

Most types of childhood dementia are caused by mutations (or mistakes) in our DNA. These mistakes lead to a range of rare genetic disorders, which in turn cause childhood dementia.

Two-thirds of childhood dementia disorders are caused by “inborn errors of metabolism”. This means the metabolic pathways involved in the breakdown of carbohydrates, lipids, fatty acids and proteins in the body fail.

As a result, nerve pathways fail to function, neurons (nerve cells that send messages around the body) die, and progressive cognitive decline occurs.

What happens to children with childhood dementia?

Most children initially appear unaffected. But after a period of apparently normal development, children with childhood dementia progressively lose all previously acquired skills and abilities, such as talking, walking, learning, remembering and reasoning.

Childhood dementia also leads to significant changes in behaviour, such as aggression and hyperactivity. Severe sleep disturbance is common and vision and hearing can also be affected. Many children have seizures.

The age when symptoms start can vary, depending partly on the particular genetic disorder causing the dementia, but the average is around two years old. The symptoms are caused by significant, progressive brain damage.

Are there any treatments available?

Childhood dementia treatments currently under evaluation or approved are for a very limited number of disorders, and are only available in some parts of the world. These include gene replacement, gene-modified cell therapy and protein or enzyme replacement therapy. Enzyme replacement therapy is available in Australia for one form of childhood dementia. These therapies attempt to “fix” the problems causing the disease, and have shown promising results.

Other experimental therapies include ones that target faulty protein production or reduce inflammation in the brain.

Research attention is lacking

Death rates for Australian children with cancer nearly halved between 1997 and 2017 thanks to research that has enabled the development of multiple treatments. But over recent decades, nothing has changed for children with dementia.

In 2017–2023, research for childhood cancer received over four times more funding per patient compared to funding for childhood dementia. This is despite childhood dementia causing a similar number of deaths each year as childhood cancer.

The success for childhood cancer sufferers in recent decades demonstrates how adequately funding medical research can lead to improvements in patient outcomes.

Another bottleneck for childhood dementia patients in Australia is the lack of access to clinical trials. An analysis published in March this year showed that in December 2023, only two clinical trials were recruiting patients with childhood dementia in Australia.

Worldwide however, 54 trials were recruiting, meaning Australian patients and their families are left watching patients in other parts of the world receive potentially lifesaving treatments, with no recourse themselves.

That said, we’ve seen a slowing in the establishment of clinical trials for childhood dementia across the world in recent years.

In addition, we know from consultation with families that current care and support systems are not meeting the needs of children with dementia and their families.

New research

Recently, we were awarded new funding for our research on childhood dementia. This will help us continue and expand studies that seek to develop lifesaving treatments.

More broadly, we need to see increased funding in Australia and around the world for research to develop and translate treatments for the broad spectrum of childhood dementia conditions.

Dr Kristina Elvidge, head of research at the Childhood Dementia Initiative, and Megan Maack, director and CEO, contributed to this article.

Kim Hemsley, Head, Childhood Dementia Research Group, Flinders Health and Medical Research Institute, College of Medicine and Public Health, Flinders University; Nicholas Smith, Head, Paediatric Neurodegenerative Diseases Research Group, University of Adelaide, and Siti Mubarokah, Research Associate, Childhood Dementia Research Group, Flinders Health and Medical Research Institute, College of Medicine and Public Health, Flinders University

This article is republished from The Conversation under a Creative Commons license. Read the original article.