Think milkshake is just a treat? Here’s how one high-fat drink can mess with your blood flow & cause permanent damage to your brain

There’s no denying the comfort of a thick, creamy milkshake or a high-fat takeaway meal. But while treating yourself now and then feels harmless, research suggests that even a single indulgence can have surprising short-term effects on your body, and your brain.

According to a study published in ScienceDirect and cited in a TOI report, scientists found that one high-fat milkshake was enough to temporarily reduce blood vessel flexibility and affect blood flow to the brain. These changes, though short-lived, highlight how quickly saturated fats can influence vascular health.

What the study found

Researchers studied two groups of men, 20 aged between 18 and 35, and 21 aged between 60 and 80. Each participant consumed a milkshake loaded with 1,362 calories and 130 grams of fat, designed to mirror a typical indulgent meal.

Using ultrasound, the team measured blood flow in the arms and brain before and four hours after the shake. Participants also performed squats so scientists could test how blood vessels responded to changes in blood pressure.

The results? Blood vessels became less flexible, making it harder for the body to regulate circulation. Older participants appeared slightly more sensitive, suggesting age can intensify these effects.

Why it matters for your brain

The brain needs a constant supply of oxygen and glucose, delivered through healthy blood flow. Normally, a process called dynamic cerebral autoregulation keeps this steady, even when blood pressure shifts.

But the study showed that high-fat meals can disrupt this balance, leading to:

• Fluctuations in blood flow to the brain
• Reduced ability of blood vessels to expand and contract
• Small rises in oxidative stress, which can affect vascular health

While the study didn’t test long-term cognitive outcomes, it confirmed that the immediate impact of a single high-fat meal is measurable.

Good fats vs bad fats

Not all fats are villains.

Saturated fats, found in milkshakes, cream, butter, and fatty meats, are the main culprits behind temporary stiffening of blood vessels.

Unsaturated fats, found in nuts, seeds, oily fish, and olive oil, actually support vascular health and reduce risks over time.

UK guidelines advise men to limit saturated fats to 30g per day, and women to 20g. A single indulgent milkshake can easily exceed this limit in one go.

How to soften the blow of indulgence

If you can’t resist the occasional shake or cheesy takeaway, there are ways to protect your body:

• Balance it out: Pair high-fat meals with vegetables, fibre, and lean protein.
• Switch fats: Opt for olive oil, avocado, or oily fish instead of cream and butter.
• Keep moving: Physical activity supports circulation and helps counter temporary stiffening.
• Hydrate well: Water keeps blood flow smooth and supports heart health.
• Don’t overdo it: Save high-fat indulgences for once in a while rather than a daily habit.

Who should be extra cautious?

Older adults, and those with high blood pressure, diabetes, or cholesterol issues, may be particularly vulnerable to the effects of fatty meals. While this study only involved men, researchers note the need to examine effects on women, who face higher risks of stroke and dementia later in life.

So, next time you’re tempted by a creamy shake, enjoy it, but remember that even one indulgence can nudge your blood vessels and brain function, at least for a few hours.

Disclaimer: This article is intended for informational purposes only and should not be taken as medical advice. Always seek guidance from a qualified healthcare professional before making changes to your diet, lifestyle, or treatment plan.