Are there any foods I should avoid?

The short answer is no. There are no foods that are known to be 'bad for bones', or that you should avoid with osteoporosis. But there are some foods that are best enjoyed in moderation.

We know there's a lot of confusing and conflicting information out there about which foods can affect your bone strength. Let's look at the facts, so you can choose your foods with confidence.

Our specialist nurses are also here if you need more information, or simply would like to talk it through.

Phytates and oxalates

Phytates and oxalates are a compound found in some common foods. They do not harm your bones directly, but can reduce the amount of calcium available to your bones by binding with calcium and other minerals that are eaten at the same time.

Phytates and oxalates are usually only found in very small amounts.

If your diet contains plenty of calcium, you don't need to worry or make any adjustments.

You may have heard soaking food can help reduce levels of phytates and oxalates, but this isn't proven and can reduce the levels of other important nutrients too.

Foods containing phytates include:

• plant foods
• bran
• nuts
• wholegrain cereals
• dried beans
• seeds
• grains

And foods containing oxalates include:

• most plant foods
• tea
• rhubarb*
• spinach*

*These contain higher levels

Learn more about phytates and oxalates: 

Dr Madhavi Vindlacheruvu tells us about whether phytates and oxalates in food reduce the amount of calcium absorbed.

Caffeine

A high-caffeine diet increases the amount of calcium lost in urine. In theory, this could lead to your bones losing strength if you don’t consume enough calcium to replace it.

This is unlikely to have a big effect on your bones.

If you drink coffee

The effect of caffeine causes only a slight imbalance between your calcium intake and calcium loss.

However, there are a few things you should think about:

• If your calcium intake is low, or you have other risk factors for osteoporosis, aim to have no more than four cups of coffee a day
• Strong, ground coffee contains more caffeine than instant coffee
• If you’re concerned, balance out the loss of calcium by drinking your coffee milky
• Remember that some soft drinks, such as cola, contain caffeine too

If you drink tea

While tea does contain caffeine, it isn't found to have the same effect on bones.

This could be because it contains other substances, such as flavonoids, that may offer a slight benefit to your bones and counteract the effects of caffeine.

An acidic diet

Some people believe foods high in proteins can cause acidity in your bloodstream.

The suggestion is your body tries to neutralise this acidity by drawing calcium salts out of your bones. Theoretically, this could cause your bones to lose strength.

People who support the theory promote using your diet to influence the pH (level of acidity) of your bloodstream. This is known as 'the alkaline diet'.

It’s true that eating plenty of fruit and vegetables has the potential to have an alkaline effect in the body and may help to balance out acid-forming foods.

However, it’s not been proven that following a strict alkaline diet, and restricting ‘acidic’ foods, lowers your risk of broken bones.

Alcohol

If you drink a lot of alcohol, your risk of osteoporosis and broken bones is significantly higher.

As you get older and become less steady on your feet, even mild intoxication increases your chances of breaking a bone through a trip or fall.

How much is too much?

The government recommends you drink no more than 14 units of alcohol a week.

In the UK, one unit is equal to eight grams of alcohol. To help you picture what this looks like, the following drinks contain one unit of alcohol:

• A single pub measure (25ml) of whisky, gin or brandy
• Half a pint of beer or cider
• A quarter of a pint of strong beer or cider

You may be surprised to know that one small glass (125ml) of table wine is one and a half units.

Try to stick to this recommendation. Although it can be tempting, don’t save up all your units for the weekend. Instead spread them out over several days.

It’s also important for you to have regular days where you don’t drink at all.

Fats

While you need some fat in your diet to support the heath of your bones, too much saturated fat potentially causes bones to lose strength.

It’s not clear why fat affects bones in this way. It’s possible that excess fat binds to calcium before it can be absorbed and used by your bones.

The link between too much fat and low bone strength could be because high-fat diets are often low in other important nutrients needed by your bones.

If you enjoy a healthy, balanced diet, including the correct proportions of fat, you don't need to be concerned.

For more information about healthy, balanced eating, we recommend you take a look at The Eatwell Guide, developed by the NHS.

Fizzy drinks

Generally speaking, fizzy drinks aren't bad for your bone health. But take care that you're not always choosing fizzy drinks over nutritious drinks, like milk.

People who drink a lot of cola may be at risk of bone loss. This could be a direct effect of phosphoric acid, which is used in cola drinks as a flavour enhancer. But it's also possible this is because people who drink a lot of cola generally enjoy a less-healthy diet.

What about the fizz?

Carbon dioxide, which gives drinks their fizz, turns into a mild acid in your body, called carbonic acid.

There is no evidence that this harms your bones.

If you enjoy fizzy water, you can continue drinking it without being concerned for your bone health.

Salt 

Excess salt may cause you to lose more calcium in your urine.

It's unclear whether this leads to your bones losing strength and an increased risk of breaking a bone.

It's still worth being aware of your salt intake, so you can make sure it's within the healthy amount.

The Department of Health recommends adults have no more than six grams of salt a day. That's equivalent to around a teaspoon.

High levels of salt are hidden in many everyday foods, including:

• bread
• breakfast cereal
• cured meats, like ham and bacon
• stock cubes
• ready meals
• processed foods

Reducing your salt intake

There are a few things you can try:

• check salt levels on the food you buy - many brands include helpful 'red, amber, green' coded nutrition information on their packaging
• reduce your intake of high-salt foods, or go for reduced salt versions instead
• be aware of how much salt you are putting in your home cooking

It can be difficult to adjust your taste buds if you’re used to salty food. Try using other strong flavours such as black pepper, fresh herbs or chilli.

Vitamin A

Research has found that if you have a high intake of a certain form of vitamin A called pre-formed retinol, your bones are more likely to lose strength.

Foods containing high levels of pre-formed retinol include:

liver and liver products, like pate
fish liver oils
Foods containing lower levels of pre-formed retinol include:

• oily fish
• milk
• cheese
• yoghurts
• fortified low fat spreads
• eggs

Vitamin A also comes in a form called beta carotene, which doesn't have a negative effect on your bones.

If you have osteoporosis

Vitamin A is still an essential part of your diet and so doesn't need to be avoided completely.

Aim to limit foods containing high levels to once a week. If this is difficult, aim to reduce your portion sizes.

Multivitamins or cod liver oil supplements

These also contain vitamin A. Having up to 1.5mg (1500 micrograms) of vitamin A from supplements or multivitamins is unlikely to cause your bones any harm.

Be aware you may be getting too much if you regularly eat foods high in vitamin A. If this is the case, it's best to stop taking your supplement or multivitamins.

Content reviewed: December 2019

(updated December 2021)