"A pillow with water in it? Won't it feel like a waterbed?" It's the first thing almost everyone asks. The short answer: no. You don't lie on the water directly, and it doesn't feel like floating. What you feel is a soft fibre pillow that somehow never flattens out from under you. The water is doing its work underneath.
Quick answer: A Mediflow water pillow has a sealed water chamber at the bottom and a layer of soft fibre on top. You add water to set the height and firmness. Because water can't be compressed but can flow, it moves to fill the space under your head and neck, then holds that support as you shift position.
What's inside a Mediflow Water Pillow
Think of it in two layers:
- Top layer: soft fibre comfort. This is what your cheek touches. It feels like a familiar, cushy pillow, under a hypoallergenic 100% cotton cover.
- Bottom layer: the Waterbase. A sealed chamber you fill with tap water using the included funnel. This is the support layer, the part that decides how high your head sits and how firmly it's held.
The pillow is jumbo size (51 × 71 cm, or 20 × 28 in) and fits a standard or queen pillowcase.
Why water? Two simple physics facts
1. Water doesn't compress. Squeeze a fibre or feather pillow and the fill squashes down and stays down. Water can't be squashed into a smaller volume. Push on it in one spot and it moves somewhere else. So the support underneath you doesn't slowly "give out" over the night the way fill does.
2. Water flows to where it's needed. When your head presses into the pillow, water moves away from the heaviest point and into the gaps around it, including the hollow under your neck. The result is support that molds to the shape of your head and neck, rather than a flat surface your neck has to bend to meet.
Put those together and you get something regular pillows struggle to do: support that is both responsive and stable. It shifts when you move, then holds.
What that feels like at 3 a.m.
Picture a typical night. You fall asleep on your back. Around 1 a.m. you roll onto your side. With a fibre pillow, your head lands in the dent where your head just was, which is now lower than you need for side sleeping, so your neck tilts down toward the mattress. Half asleep, you bunch the pillow up under your ear.
With a Waterbase pillow, when you roll, the water redistributes under your new position. The pillow reshapes itself to the side-sleeping profile without you having to wake up and fix it. No more fighting with your pillow at 3 a.m.
You set the support level
Because you control how much water goes in, you control the feel:
| Feel | Approximate water | Often suits |
|---|---|---|
| Soft | about 2 L (2 qt) | Stomach sleepers, smaller frames |
| Medium | about 3 L (3 qt) | Back sleepers |
| Firm | about 4–5 L (4–5 qt) | Side sleepers, broader shoulders |
Most people find their sweet spot after a few nights of small adjustments. Our step-by-step fill guide walks you through it.
Does it actually help neck pain?
Water pillows aren't a new gimmick; they've been studied. In a randomized crossover trial led by researchers at Johns Hopkins, 41 people with neck pain each tried three pillows: their usual pillow, a roll pillow and a water-based pillow. On the water-based pillow, participants reported less morning pain, more pain relief and better sleep quality (Lavin, Pappagallo & Kuhlemeier, Archives of Physical Medicine and Rehabilitation, 1997). We dig into that study in an upcoming post.
FAQ
Does a water pillow slosh? Most of the sound and movement settles once the pillow is filled to your level and you've removed extra air while capping it. The fibre top layer also cushions movement.
Does a water pillow feel cold? The water sits beneath a thick fibre layer, so you don't feel the water temperature directly. It feels like a regular soft pillow.
Is a water pillow heavy? That depends on how much water you add. Empty, the pillow weighs about 0.9 kg (2 lb); each litre of water adds about 1 kg (2.2 lb). So it's heavier than a standard pillow, which also helps it stay put on the bed.
Curious what water-based support feels like? Try the Mediflow Water Pillow for 30 nights. It also comes with a 3-year warranty.
This article is for general information and isn't medical advice. If you have ongoing or severe neck pain, please talk to a healthcare professional.