Which side of the aluminum foil should you use for cooking: the shiny side or the matte side?

Glossy or matte? The answer is simpler than you might think — and could well put an end to an old debate in the kitchen.

Admit it: you've hesitated in front of your roll of aluminum foil. Shiny side up? Matte side down? We've all heard a different theory, often passed down like a grandmother's secret. Yet, the answer is much simpler than you think… and it might surprise you.

Glossy or matte: is there a real difference?

Look at your aluminum foil: one side is smooth and shiny, the other slightly more matte. Instinctively, we think that one must cook better than the other.

In reality? Not at all.

For conventional oven cooking, both sides function in exactly the same way. They conduct heat identically and do not influence either the temperature or the cooking of the food.

So you can use whichever side you prefer, without fear of ruining your gratin or your fish en papillote.
 

Why are there two different sides then?

The difference does not come from special treatment, but from the manufacturing process.

During lamination, two layers of aluminum are pressed simultaneously between rollers to obtain a very thin and strong sheet. The side in contact with the rollers becomes shiny, while the other, in contact with the second sheet, remains more matte.

This is simply a mechanical effect, not a special feature.

In other words: no mystery, just industrial technique.

The only exception is non-stick aluminum.

However, there is one exception.

Some rolls are labeled “non-stick”. In this case, one side has a treatment designed to limit food sticking.

And it's usually the matte side.

Manufacturers indicate this on the packaging. If your roll is marked “non-stick”, check the instructions and place the treated side in contact with the food to benefit from the non-stick effect.

Otherwise, you can continue to package your vegetables, meats or desserts without asking any questions.

Should one side be favored for better cooking?

Some misconceptions suggest that the shiny side reflects more heat. In practice, in a domestic oven, the difference is minimal and imperceptible.

Heat circulates mainly by convection (hot air) and conduction (direct contact with the dish or food), much more than by reflection.

So whether you are preparing a salmon papillote, roasted vegetables or covering a dish to prevent it from browning too quickly, the result will be the same with  cooking foil  used in either direction.

A quick practical reminder

Even if the side doesn't matter much, a few simple rules allow you to use  aluminum foil  safely:

Avoid prolonged direct contact with highly acidic foods (lemon, tomato) at high temperatures, as the acidity can slightly alter the metal.

Never use it in the microwave: this causes sparks and can damage the device.

Do not place it in direct contact with the heating elements or the walls of the oven to avoid any risk of overheating.

Following these precautions ensures safe use and optimal cooking.

The next time you unroll your aluminum foil, you can do so with peace of mind: shiny or matte, the choice is yours.

Reaching 60 in good health: factors associated with greater longevity.

 Longevity is not determined by genetics alone. One of the strongest predictors of how long—and how well—you will live is which illnesses you have managed to avoid. When someone reaches their 60s, 70s, or even 80s without certain chronic conditions, it’s a powerful sign that their body systems are still working in harmony, with resilience and the ability to repair themselves.

There are five major diseases that most often shorten life after age 60. If you do not have them, you are already on a favorable path toward a long, active life.
1. Heart disease
The heart is the body’s central engine. When it weakens, other organs soon follow. Most heart problems don’t appear suddenly—they develop slowly over many years due to high blood pressure, stiffened arteries, and impaired circulation.
If you’ve passed age 60 without heart attacks, serious rhythm disorders, or coronary disease, it suggests your arteries remain flexible, your blood flows efficiently, and your heart is not under excessive strain.

A strong heart also supports memory, energy levels, and emotional balance. When circulation is healthy, aging throughout the body slows down.

2. Diabetes

Diabetes affects far more than blood sugar. Over time, it damages blood vessels, nerves, kidneys, eyes, and even the brain, accelerating internal aging.

Reaching older age without diabetes indicates that your metabolism is still functioning effectively. Your body can regulate energy, manage inflammation, and repair tissues more efficiently.

This translates into healthier circulation, better nerve function, less kidney stress, and clearer thinking as the years go by.

3. Str0ke and circulation disorders
Strokes occur when blood supply to the brain is blocked or when a vessel ruptures. Even when not fatal, they can severely impact speech, movement, memory, and independence.

If you’ve avoided strokes and major circulation problems, it’s a sign that your vascular system remains strong. Your arteries can still adapt, delivering oxygen and nutrients throughout your body.

Good circulation is essential for staying mentally sharp and physically capable in later life.

4. Can.cer
Cancer develops when cells lose control over their growth. Abnormal cells form every day, but a healthy immune system usually identifies and eliminates them before they become dangerous.

Reaching old age without cancer suggests that your cellular defense mechanisms are still effective. Your body continues to recognize and neutralize internal threats.