Is White Residue On Dishes Harmful? – 6 Possible Reasons and How to Eliminate Them

We all expect the dishwasher to make our dishes sparkling clean. Instead, we are sometimes faced with the fact that a chalky white film has formed on our kitchenware during the washing cycle.

Have you ever wondered if the white film on dishes is harmful to your health? The purpose of my post is to find out if these deposits are toxic, and how can we prevent them from appearing on our kitchenware.

The white residue on dishes is not harmful to health if it is caused by mineral deposits in hard water, mostly calcium and magnesium.

If the white film on the dishes is caused by detergent residue, it can be harmful in large quantities, as it can cause throat irritation and an upset stomach. Dishwasher detergents are more concentrated and much more aggressive than dish soap used for manual washing.

What can cause the chalky white residue on dishes?

In the majority of cases, the minerals in the hard water are the cause of the white residue on the dishes.

Chalky residue on dishes can be caused by too much dishwasher detergent, as well as the lack of rinse aid. Detergent can also remain on the dishes if the dishwasher does not get enough water. Talking of detergent residue, you may wish to read my article on what happens if you don’t rinse your dishes properly.

White marks on kitchenware can rarely be caused by dishwasher salt. This can happen if the cap of the salt container is not properly sealed, or if it is broken and leaking.

We can prevent the formation of white residue on our dishes if we determine what causes it by examining the possible reasons.


1. Mineral deposits caused by hard water

If the water in your area is hard, the minerals in it will form deposits both in the dishwasher and on the dishes. Detergent won’t work with full efficiency in hard water either.

Dishwashers usually have a water softening system, which must be filled with special salt. Dishwasher salt differs from ordinary table salt and sea salt in that it has finer grains. Do not use fine-grained salt instead, as it can cause clogging.

The sodium in the dishwasher salt eliminates the calcium and magnesium in the incoming water by ion exchange. The dishwasher salt, therefore, prevents mineral residue on the dishes and also protects the dishwasher components.

If you descale your dishwasher every two or three months, it will reduce the white marks on your dishes and extend the machine’s life span. The best way to descale your dishwasher is to wash it with the cleaning and descaling agent available specifically for this purpose.

However, if you live in an area with soft water, do not use salt as it can cause corrosion of the dishes. You can get information about water hardness from your water supplier.

3. You are not using the right type or amount of dishwasher detergent

New-generation pods and tablets make it easy to dose the detergent, but they may not be the best for the dishwasher because you can’t adjust the size of the dose.


If you use pods or capsules and they cause deposits on your dishes and inside the dishwasher, you may want to try a powder or liquid detergent and experiment with the dosage. Too much detergent accumulates in the dishwasher drains and can cause blockages.

By using less detergent, the white residue on your dishes will usually disappear and the dishwasher will be cleaner. Experiment with reducing the amount, because you may not need as much as the manufacturer’s instructions recommend. New-generation dishwashers work with little water and therefore require less detergent.

If the water in the area where you live is hard, you probably need to use more dishwasher detergent than if the water is soft. However, it is important to note that you should only use dishwasher detergent. Detergents for manual dishwashing or laundry produce a lot of suds, so they should not be used in the dishwasher. Dishwasher detergent is not sudsy.

If there is an undissolved, caked residue left in the detergent dispenser of the dishwasher, it must be cleaned before refilling for the next cycle.

Why should you add salt to your dishwasher

3. The dishwashing detergent is too old or it was stored in an inadequate place

Dishwasher detergent loses its effectiveness over time or when stored improperly. According to the Finish dishwasher manufacturer, it is best to use up the detergent within two years and store it in a dry place in a well-sealed container. So, it is not worth accumulating a large amount of it. Powdered detergent stored in a damp place will clump and will not dissolve sufficiently in the dishwasher.

4. You don’t use rinse aid at all, or you use it in an inadequate amount

The rinse aid helps the water drops to roll off the washed dishes more easily. This leaves less water on the dishes and fewer white marks. By using a rinse aid, dishes dry faster and become shiny. Adding agents containing citric acid can also help eliminate the appearance of white deposits on dishes.


The rinse aid dispenser is located on the door of the dishwasher, next to the detergent dispenser. The dosage of the rinse aid can be regulated. With a little experimentation, you can set the right amount for your dishwasher.

If the dishes, especially the glasses, are cloudy and have a white film on them, then the amount should be increased. If, on the other hand, you see rainbow-like discoloration on your kitchenware, you should reduce the amount of rinse aid.

5. The dishwasher is not getting enough water or it is not hot enough

If your dishwasher doesn’t get a sufficient amount of water, it can’t wash effectively, and there may be residue on the dishes after the washing cycle. The reason for the insufficient amount of water in the dishwasher can be clogged spray arms, a faulty water pump, or clogged pipes.

According to Finish, the water temperature in the dishwasher must be above 50°C/122°F for the detergent to dissolve and perform well.

6. The dishwasher salt accidentally got into the dishwasher cavity

Dishwasher salt cannot normally enter the dishwasher cavity, as it is only used by the water softening system. However, it may still end up on the dishes during washing, mostly if the lid of the container is not properly closed or if it is broken.

When pouring the salt into the container at the bottom of the dishwasher, make sure to wipe off any spilled water and salt. After the salt has been poured into the container and sealed, it is recommended to rinse the inside of the machine with a short washing cycle, which dissolves and removes the remaining salt particles.


Final Thoughts

The white deposit left by the dishwasher is mostly formed by the minerals in the hard water and is not harmful to health. By using a rinse aid and dishwasher salt and by regularly cleaning the machine, you can reduce the amount of scale that forms.

If, on the other hand, the dishwasher detergent is the cause of the white deposits on your dishes, it can even be harmful in larger quantities. In such cases, it can be a good solution if you use less detergent or try a different type.



My name is Debora, the founder of My Delicious Sweets, and a qualified confectioner with broad experience in the confectionery industry. On my blog, I will share important, interesting, and fun facts about food, along with some of my favorite recipes.

Leave a Comment