25/08/2026
While the rest of the team are off enjoying themselves in the Maldives, the USA and various other glamorous locations, I had to settle for fish and chips in Ashbourne last night! 😂
The person looking after me said they normally have a glass of milk after fish and chips because milk is more hydrating than water.
My immediate thought was:
“That sounds completely bonkers…”
But annoyingly, they may have been right!
Researchers compared 13 different drinks by asking 72 men to drink one litre, then measuring how much fluid their bodies retained over the following four hours.
The drinks that performed particularly well were:
🥇 Oral rehydration solution
🥛 Skimmed milk
🥛 Full-fat milk
💧 Water — used as the benchmark
Milk appeared to keep people hydrated for longer because it contains sodium, potassium, carbohydrate and protein. These can slow the movement of fluid through the stomach and help the body retain more of it, rather than quickly passing it out as urine.
Interestingly, tea and coffee still hydrated people and performed similarly to water in this experiment. The caffeine didn’t magically cancel out all the fluid, as we’re sometimes told.
Orange juice, cola and sports drinks also provided hydration—but weren’t significantly better than water over the full four hours.
And there’s another twist…
🍟 The salt in the meal may also have helped the body retain some of the fluid consumed with it.
So perhaps fish, chips and a glass of milk isn’t a nutritional disaster—it’s an advanced hydration strategy!
That’s the excuse I’m using anyway. 😂
However, this doesn’t mean we should replace every glass of water with milk. Milk contains calories, may not suit people with lactose intolerance, and the main study only involved 72 healthy men who were already adequately hydrated. It measured short-term fluid retention—not which drink was healthiest overall.
For everyday hydration, water remains cheap, effective and calorie-free. The NHS also confirms that lower-fat milk, tea, coffee and sugar-free drinks all count towards our daily fluid intake.
References
Maughan RJ et al. A randomized trial to assess the potential of different beverages to affect hydration status: development of a beverage hydration index.* American Journal of Clinical Nutrition, 2016. [Read the study](https://pubmed.ncbi.nlm.nih.gov/26702122/)
Shirreffs SM et al. Milk as an effective post-exercise rehydration drink. British Journal of Nutrition, 2007. [Read the study](https://www.cambridge.org/core/journals/british-journal-of-nutrition/article/milk-as-an-effective-postexercise-rehydration-drink/B358D6BE20736AF3DA0373D63E72CC65)
[NHS guidance on water, drinks and hydration](https://www.nhs.uk/live-well/eat-well/food-guidelines-and-food-labels/water-drinks-nutrition/)