Just one bowl of cereal a day ‘increases your risk of dementia’ – as key ingredient blamed
CRUNCHING on just one bowl of your favourite cereal a day might raise your risk of dementia, research suggests.
Scientists have found a link between high levels of thiamine – a vitamin commonly added to breakfast cereals – and cognitive decline.
One in 10 people who experience mild cognitive impairment go on to develop dementia, according to Alzheimer’s Research UK.
Thiamine, also known as vitamin B1, helps turn food into energy and keep the nervous system healthy, the NHS says.
Your body doesn’t make it by itself, but you can usually get all you need to the vitamin from your diet.
It’s found naturally in some foods, added to others and sold in supplement form too.
Thiamine is often added to cereals like corn flakes and frosted flakes, as well as bread and baby formulas.
According to the Harvard T. H. Chan School of Public Health, foods that commonly contain the vitamin are:
- Fortified breakfast cereals
- Pork
- Fish
- Beans and lentils
- Green peas
- Enriched cereals, breads, noodles, rice
- Sunflower seeds
- Yogurt
Research has previously linked a deficiency in thiamine to neurological problems like cognitive decline.
One form of thiamine deficiency is called Wernicke-Korsakoff syndrome and causes cognitive changes similar to Alzheimer’s disease.
Studies conducted on animals have suggested that a lack of thiamine may cause oxidative stress or the death of nerve cells, memory loss, formation of plaque, and reduced glucose metabolism, which are all risk factors for Alzheimer’s disease.
But research in humans has been limited.
Now, a new study published in the journal General Psychiatry also linked higher thiamine intake to cognitive decline, especially in people who had high blood pressure or were obese.
Researchers looked at data from the China Health and Nutrition Survey, which asked 3,016 adults to report their diets and repeat cognitive function tests – these included word recall and number pattern challenges.
Participants’ average age was 63.
As they followed up with participants after about five years, researchers found a J-shaped curve association between thiamine consumption and a decline in cognitive test scores.
The J-shaped curve means that two little of thiamine or too much of it can have adverse effects, but researchers pinpointed an ideal amount of thiamine between the two.
On average, study participants consumed 0.93 mg per day.
Researcher’s analysis found that the ideal amount was 0.68 mg per day, but between 0.6 mg and 1.00 mg per day had minimal risks.
However, every 1.0 mg per day above the safe limit of 0.68 mg was associated with a fall of 4.24 points on in cognitive scores.
However, an average bowl of most fortified breakfast cereals contains more than the sweet spot of 0.68 mg.
The National Institutes of Health report that one serving contains 1.2 mg of thiamine.
The study team wrote: “Beyond the inflection point of dietary thiamine intake, thiamine intake was significantly positively associated with cognitive decline.
“This finding is consistent with our recent studies, which found that long-term excessive intake of thiamine was associated with an increased risk of new-onset diabetes and new-onset hypertension in
the general population.
“This series of studies consistently shows that excessive intake of thiamine may have adverse health effects on Chinese adults.
“Of note, both diabetes and hypertension are risk factors for cognitive decline or dementia.”
They explained that thiamine can regulate levels of acetylcholine – a neurotransmitter that plays a role in memory, learning and attention – by inhibiting the activity of the enzyme cholinesterase.
“High levels of acetylcholine in the brain can adversely affect cognition,” researchers said.
“Therefore, we speculate that high levels of dietary thiamine intake may lead to cognitive decline by inducing elevated levels of acetylcholine in the brain.”
But they noted that more research is needed to confirm their results.
Who is particularly at risk?
Researchers also noted that the link between thiamine intake and cognitive decline was stronger in individuals with hypertension – as high blood pressure is also known – and obesity.
“Hypertension and obesity are established risk factors for cognitive decline, which could impair cognitive function by affecting cerebrovascular structure and central inflammation, respectively,” they said.
The study team said they findings emphasised the importance of avoiding excessive thiamine intake for people with high blood pressure or obesity.
What are the early symptoms of cognitive decline?
WE all notice a natural decline in memory and thinking as we age.
This will be more pronounced in some people, as they experience memory and thinking problems that are mild but still noticeable.
This is described as mild cognitive impairment (MCI). Unlike dementia sufferers, people with MCI can still get on with day-to-day life.
Research suggests that two out of 10 people over the age
of 65 have MCI, according to Alzheimer’s Research UK.
About one in 10 people who’ve received an MCI diagnosis will go on to develop dementia.
Symptoms of MCI include:
Memory – Misplacing items or having trouble
remembering recent conversations.
- Attention problems – finding it difficult to concentrate,
e.g. while watching a TV programme or carrying out
duties at work - Disorientation – confusion about time, date or place
- Thinking skills – problems with planning or completing
tasks, e.g. managing money, or cooking a meal - Problems with communication and finding the right words
- Mood and behaviour changes – becoming irritable, anxious,
or feeling low
These symptoms may affect someone with MCI all the
time, or they might come and go.
There are steps we can take to keep our brains as healthy as possible These include:
- Not smoking
- Doing regular physical activity
- Staying mentally and socially active
- Eating a healthy balanced diet
- Limiting the amount of alcohol we drink
- Having your hearing checked regularly
- Keeping blood pressure, blood sugar and cholesterol
levels in check