The plot thickens …
New research suggests that we pay a higher price for our high-fat indulgences than previously thought — even just one milkshake can impair blood flow to the brain, increasing the risk of stroke and dementia.
“As we’re learning, when it comes to protecting brain health, every meal may count,” researchers Chris Marley and Damian Bailey of the University of South Wales recently wrote in The Conversation.
We all need fat to function — it provides energy, warmth and protection for our organs.
Saturated and unsaturated fats are chemically different and have vastly different effects on our bodies.
Meals high in saturated fat cause blood fat levels to rise and blood vessel walls to stiffen, which can impair blood flow and force the heart to work harder. These effects peak four hours after consumption.
Researchers were keen to discover how this combination of factors affects the brain.
Recruiting 20 men between the ages of 18 and 35 and 21 men between 60 and 80, researchers measured the effectiveness of blood vessels linked to heart and brain health before and after consuming a milkshake dubbed the “brain bomb.”
The decadent shake clocked in at 1,362 calories and 130 grams of fat, as the primary ingredient was heavy whipping cream.
“Our findings confirmed previous research that has shown that a high-fat meal impairs the ability of the blood vessels linked to heart health to open in both young and old participants,” Marley and Bailey wrote.
“These impairments reduced the brain’s ability to buffer changes in blood pressure,” they added. “This was more pronounced (by about 10%) in the older adults, suggesting that older brains may be more vulnerable to the effects of the meal.”
The pair noted that previous research has shown that meals high in saturated fat increase cell-damaging free radicals while decreasing nitric oxide, which helps relax blood vessels and supports the transport of oxygen and glucose throughout the body.
That’s why the American Heart Association recommends limiting saturated fat to less than 6% of total daily calories.
For someone who eats 2,000 calories a day, that means no more than 120 calories — or roughly 13 grams — should come from saturated fat.
That limit is easy to exceed. Just one tablespoon of butter has about 7 grams of saturated fat, while two slices of bacon pack in roughly 3 grams.
Experts recommend trading saturated fats for polyunsaturated ones, like those found in oily fish, walnuts, seeds, avocado and olive oil, which have been linked to a reduced risk of heart disease.
Still, Marley and Bailey caution that they do not know how the brain responds to meals high in polyunsaturated fat.
They also acknowledged that one of the primary limitations of their study is that it doesn’t account for how the female brain responds to a meal high in saturated fat.
“This is a crucial gap in our knowledge since women face a greater risk of stroke and dementia in later life compared to men,” they said.
They are nevertheless hopeful their findings will illustrate how important proper nutrition is in the immediate and long term.
“Our study offers a timely reminder that diet doesn’t just shape our long-term health. It also affects our body and brain in real time,” they wrote.
Read the full article here
