An undershirt ("maglia della salute") is an intimate garment worn against the skin, under a shirt or sweater, to keep you warm all day long when you are stationary, at the office, or at home. It used to be made of thick wool. Today, there are thin versions made of merino wool, with cashmere, and in bamboo viscose, which are invisible under clothes.

Why is it called "maglia della salute" (health shirt)?

The name comes from the idea of protecting the torso from the cold and from temperature fluctuations, such as those encountered when moving from home heating to public transport, the street, or the office. It is a common name, without medical significance: the shirt simply keeps you warm.

The difference compared to the past is the thickness. A seamless shirt, with no side seams, fits under a shirt without showing lines and under a sweater without adding bulk, so you can wear it every day, even with elegant outfits.

What material should it be made of today?

It depends on how cold you feel and what you are wearing over it. The table compares the three materials Risalti uses for this type of garment.

Cashmere is a percentage of the composition: 10% in the Light Cashmere Tank Top (the rest is 90% modal), 6% in the mock neck (70% polyamide, 24% viscose). These are garments enriched with cashmere, which is where the softness comes from. The merino wool shirt has extra-fine merino wool on the outside and polypropylene on the inside, against the skin (46% polypropylene, 28% wool, 22% polyamide, 4% elastane). The bamboo tank top is 80% bamboo viscose, 14% polyamide, 6% elastane.

As a rule of thumb: if you feel the cold mostly outdoors, start with merino wool. If you spend your days in heated environments and just want an extra layer, cashmere or bamboo are sufficient. For delicate skin, bamboo is the most sensible starting point.

Undershirt or thermal shirt: what's the difference?

An undershirt is for staying warm while stationary; a technical thermal shirt is for managing sweat while you are moving. A lightweight thermal garment like the Energy line works well at the gym or during a brisk walk. At a desk, or waiting in line in the cold, you need a garment that insulates and can be forgotten about while wearing it all day. The two shirts do not replace each other: those who work in an office can wear an undershirt all day and keep a thermal shirt for the gym in the evening.

Risalti makes both, and merino wool is the middle ground: the internal polypropylene keeps the skin dry, while the wool on the outside warms at temperatures from 0°C to -15°C. The details are in the merino wool thermal shirt guide, while the women's thermal shirt guide explains how to choose based on activity.

Tank top, short sleeve, or long sleeve?

The choice depends on what you wear over it. A tank top under a shirt is the most discreet: it doesn't add bulk to the sleeves and is not visible. In the women's tank top collection, you will find the Light Cashmere Tank Top, designed to be worn under oversized blazers, maxi-sweaters, and cardigans, as well as wide-strap or thin-strap bamboo tank tops.

If you are looking for a wool tank top, Risalti does not have one in merino wool: merino wool is available in short-sleeve and long-sleeve shirts. The short sleeve fits under a shirt. The long sleeve is for real cold, and the mock neck with cashmere adds a high collar. The Light Cashmere line also includes a long-sleeve shirt and a turtleneck.

The wide strap is comfortable under shirts, sweaters, and t-shirts. The thin strap is better for dresses with thin straps and more open necklines. Under a turtleneck or crewneck sweater, any tank top will do, so choose based on the fabric and the desired level of warmth.

Women's vs. men's intimate apparel: what changes?

The selection of women's intimate apparel is broader: at the moment, garments with cashmere are only for women, and you can find them together with the rest in the women's knitwear collection. For men, there is the Men's Short-Sleeve Merino Wool Thermal Shirt and the Men's Wide-Strap Bamboo Tank Top, in the men's knitwear collection. A men's undershirt is usually a tank top or a short-sleeve shirt to wear under a dress shirt.

The fit is the same: the seamless garments are close-fitting, never oversized, and if you are between two sizes, it is better to go with the larger one. Merino wool fits about one size larger than the Energy line: if you wear an S/M in the Energy line, go for an XS/S in merino wool.

How to wash them to make them last?

All the garments in this guide should be washed at 30°C, as indicated on each product page. Full instructions, including those for merino wool, are in how to wash seamless intimate apparel and merino wool.

Frequently Asked Questions

Is the undershirt worn directly against the skin?

Yes, it is worn directly against the skin as the first layer under a shirt or sweater. That is why the fabric matters: Risalti garments are seamless, with no side seams, and bamboo viscose is very soft and suitable even for sensitive skin.

Can it be worn to bed?

Yes, it is just a matter of comfort. If you use it for sleeping, a bamboo tank top or a garment with cashmere is better, as they are lighter than the merino wool shirt.

Does merino wool itch?

It depends on each person's skin. In Risalti shirts, the extra-fine merino wool is on the outside, and there is an internal layer of polypropylene against the skin. If you have very reactive skin, try a bamboo or cashmere garment first.

What size should I choose?

The one that corresponds to your usual size: the garments are close-fitting and not oversized. If you are between two sizes, go with the larger one. You will find the size guide on every product page.