How to wash your hands

Washing your hands is one of the easiest ways to protect yourself and others from illnesses such as food poisoning and flu.

But what's the best handwashing technique?

Washing your hands properly should take about as long as singing "Happy Birthday" twice (around 20 seconds). Use the following steps from the World Health Organization while you hum:

1. Wet your hands with water (warm or cold).

2. Apply enough soap to cover all over your hands. You can use alcohol-based handrub if you don't have immediate access to soap and water.

3. Rub hands palm to palm.

4. Rub the back of your left hand with your right palm with interlaced fingers. Repeat with the other hand.

5. Rub your palms together with fingers interlaced.

6. Rub the backs of your fingers against your palms with fingers interlocked.

7. Clasp your left thumb with your right hand and rub in rotation. Repeat with your left hand and right thumb.

8. Rub the tips of your fingers in the other palm in a circular motion, going backwards and forwards. Repeat with the other hand.

9. Rinse hands with water (warm or cold).

10. Dry thoroughly, ideally with a disposable towel.

11. Use the disposable towel to turn off the tap.

How often should we wash our hands?

We should wash our hands:

• after using the toilet
• after handling raw foods like chicken, meat and vegetables
• before eating or handling ready to eat food
• after having contact with animals, including pets

Why is it so important to wash hands properly?

Washing your hands properly removes dirt, viruses and bacteria to stop them spreading to other people and objects, which can spread illnesses such as food poisoning, flu or diarrhoea.

"Hands are easily contaminated with faecal bacteria [poo] when going to the toilet and this can be easily spread on to other things you touch, including food," says Professor Jeremy Hawker, a consultant epidemiologist at Public Health England.

"Unfortunately, not all people consistently wash their hands after going to the toilet or before handling food.

"Washing your hands with soap and water is sufficient to remove dirt, viruses or bacteria and it can reduce the risk of diarrhoea by nearly 50%."

Who is most at risk from the effects of poor hand hygiene?

Children are particularly at risk of picking up infections and spreading them to other people.

It's especially important to make sure that hands are washed when you're visiting someone in hospital or other healthcare setting, to help prevent the spread of infection.

Watch this video to see the handwashing technique in action.

How to store food and leftovers

Tips on storing food and leftovers to prevent food poisoning, including:

• fridge storage
• "use-by" dates
• freezing food
• storing eggs
• storing meat and poultry
• freezing and defrosting
• using leftovers
• re-using plastic bags

What goes in the fridge?

Some foods need to be kept in the fridge to help slow down germs' growth and keep food fresh and safe for longer.

These are foods marked with a "use by" date and "keep refrigerated" on the label, such as milk, meat and ready meals.

Cool down leftovers as quickly as possible (ideally within two hours), store them in the fridge and eat them within two days.

It is safe to let food cool completely at room temperature before storing it in the fridge.

Avoid putting open tin cans in the fridge, as the food inside may develop a metallic taste.

Follow the manufacturer's instructions or place the contents in a storage container or covered bowl before refrigerating.

Fridge maintenance

Keep your fridge temperature at 5C or below.

If your fridge has a digital temperature display you may wish to check it against an internal fridge thermometer now and again to make sure it's accurate.

Clean and inspect your fridge regularly to ensure it remains hygienic and in good working order.

"Use-by" dates

No food lasts forever, how ever well it is stored. Most pre-packed foods carry either a "use-by" or a "best before" date.

• "Use-by" dates appear on foods that go off quite quickly. It can be dangerous to eat foods past this date.
• "Best before" dates are for foods with a longer life. They show how long the food will be at its best.

Food can look and smell fine even after its "use-by" date but that doesn't mean it's safe to eat. It could still contain bugs that could make you ill.

Eating food past its "best before" date is not dangerous, but the food may not be good quality.

Freezing food

You can freeze pretty much everything, including:

• yogurt
• cheese (except soft cheese as the freezing process affects the texture)
• milk
• meat
• fish
• eggs, including boiled eggs
• bananas: peel and wrap them or place in an air tight container before freezing
• baked goods
• rice: read our safety tips
• bread

Anything with a high water content like strawberries and tomatoes will go squishy but are still fine to cook with.

Place food in an air-tight container or wrap it tightly in freezer bags or similar before placing in the freezer otherwise the cold air will dry it out.

Storing eggs

Eggs are best stored in the fridge as they are kept at a constant temperature.

Eggs can also be frozen. Two ways to freeze eggs:

• crack the egg and separate yolks and whites into separate plastic containers or food bags before freezing. This is handy for baking.
• crack the egg into a plastic tub and beat it before freezing - great for omelettes and scrambled eggs.

You can safely store a boiled egg in the fridge for a couple of days. Boiled eggs can also be frozen.

Storing meat and poultry

It's important to store meat safely in the fridge to stop bacteria from spreading and avoid food poisoning.

• Store raw meat and poultry in clean, sealed containers on the bottom shelf of the fridge.
• Follow any storage instructions on the label and don't eat meat after its use-by date.
• Keep cooked meat separate from raw meat and ready to eat foods in general.

It's safe to freeze meat and fish as long as you:

• freeze it any time before its use-by date
• defrost meat and fish thoroughly before cooking – lots of liquid will come out as meat thaws, so stand it in a bowl to stop bacteria in the juice spreading to other things
• defrost meat or fish in a microwave if you intend to cook straight away, or if not, defrost in the fridge overnight so it doesn't get too warm
• cook food until it's steaming hot throughout

Make sure meat is properly wrapped in the freezer or it might get freezer burn, which can make it tough and inedible.

Date and label meat in the freezer and eat it within 24 hours of defrosting.

You can freeze meat for a long time and it will still be safe to eat, but the quality will deteriorate so it's best to eat it within three to six months.

Don't worry if it's frozen for longer – try marinating it before cooking to improve texture or use herbs and spices to add flavour.

Re-freezing meat and fish

Never re-freeze raw meat (including poultry) or fish that has been defrosted.

You can cook frozen meat and fish once defrosted, and then refreeze them.

You can re-freeze cooked meat and fish once, as long as they have been cooled before going into the freezer. If in doubt, don't re-freeze.

Frozen raw foods can be defrosted once and stored in the fridge for up to 24 hours before they need to be cooked or thrown away.

To reduce wastage, divide the meal into portions before freezing and then just defrost what you need.

Using leftovers

Don't throw away leftovers: they could be tomorrow's lunch! Follow these tips to make the most of them:

• Cool leftovers as quickly as possible, ideally within two hours.
• Divide leftovers into individual portions and refrigerate or freeze.
• Use refrigerated leftovers within two days.
• When reheating food, make sure it is heated until it reaches a temperature of 70C for two minutes, so that it is steaming hot throughout.
• Always defrost leftovers completely, either in the fridge or in the microwave.
• When defrosted, food should be reheated only once, because the more times you cool and reheat food, the higher the risk of food poisoning.
• Cooked food that has been frozen and removed from the freezer should be reheated and eaten within 24 hours of fully defrosting.
• Foods stored in the freezer, such as ice cream and frozen desserts, should not be returned to the freezer once they have thawed.
• For safety and to reduce waste, only take out of the freezer what you intend to use within the next 24 hours.

Re-using bags

With more people re-using single-use plastic carrier bags or using a reusable bag for life, you can help prevent bacteria spreading to ready-to-eat food by:

• packing raw foods separately from ready-to-eat foods, in separate bags
• keeping one or two reusable bags just for raw foods only – don't use the same bags for ready-to-eat foods
• checking your bags for spillages, such as raw meat juices or soil, after every use

If there has been any spillage, soiling or damage, plastic bags for life or single-use plastic carrier bags should ideally be disposed of.

Cotton and fabric-based bags for life can be put in the washing machine.

Acesulfame K: the evidence

Acesulfame potassium, also known as acesulfame K, is a calorie-free sweetener up to 200 times sweeter than sugar and as sweet as aspartame.

It is often blended with sucralose and used to decrease the bitter aftertaste of aspartame.

A wide range of low-calorie foods and drinks contain acesulfame K, including table-top sweeteners, chewing gum, jam, dairy products, frozen desserts, drinks and baked goods.

Acesulfame K is not broken down when digested, nor is it stored in the body. After being consumed, it is quickly absorbed by the body and then rapidly excreted, unchanged.

Acesulfame K has been approved for general use in the EU and the US. Critics say the sweetener has not been studied adequately and may be carcinogenic, affect pregnancy and cause tumours.

The US Center for Science in the Public Interest (CSPI) has questioned the quality of the research on cancer. However, these claims have been dismissed by the US Food and Drug Administration and the European Food Safety Authority (EFSA).

The EFSA's predecessor, the Scientific Committee on Food, re-examined the cancer studies in 2000 (PDF, 41kb) and concluded there was no "indication of possible carcinogenicity from these studies".

The reviewing panel also concluded that acesulfame K was not toxic at recommended levels of consumption and could not cause gene mutation.

Acceptable daily intake: 9mg per kg of body weight

Find out what the latest scientific evidence says about these other common artificial sweeteners:

• aspartame
• saccharin
• sucralose
• steviol glycosides (stevia plant extracts)
• xylitol
• sorbitol

Read The truth about sweeteners

The truth about sweeteners

Artificial sweeteners are low-calorie or calorie-free chemical substances that are used instead of sugar to sweeten foods and drinks.

They are found in thousands of products, from drinks, desserts and ready meals, to cakes, chewing gum and toothpaste.

Find out what the evidence says on the safety of some of the most common sweeteners approved for use in the UK:

• acesulfame K
• aspartame
• saccharin
• sorbitol
• sucralose
• stevia (steviol glycosides)
• xylitol

Both Cancer Research UK and the US National Cancer Institute have said sweeteners don't cause cancer.

"Large studies looking at people have now provided strong evidence that artificial sweeteners are safe for humans," states Cancer Research UK.

All sweeteners in the EU undergo a rigorous safety assessment by the European Food Safety Authority (EFSA), before they can be used in food and drink.

As part of the evaluation process, the EFSA sets an acceptable daily intake (ADI), which is the maximum amount considered safe to consume each day over the course of your lifetime.

You don't need to keep track of how much sweetener you consume each day, as our eating habits are factored in when specifying where sweeteners can be used.

Are sweeteners healthy?

Sweeteners may be safe, but are they healthy? Food manufacturers claim sweeteners help prevent tooth decay, control blood sugar levels and reduce our calorie intake.

EFSA has approved the health claims made about xylitol, sorbitol and sucralose, among others, in relation to oral health and controlling blood sugar levels.

Dietitian Emma Carder states: "Research into sweeteners shows they are perfectly safe to eat or drink on a daily basis as part of a healthy diet."

She also says they are a really useful alternative for people with diabetes who need to watch their blood sugar levels while still enjoying their favourite foods.

"Like sugar, sweeteners provide a sweet taste but what sets them apart is that, after consumption, they don't increase blood sugar levels," she says.

It has been suggested that the use of artificial sweeteners may have a stimulating effect on appetite and, therefore, may play a role in weight gain and obesity.

However, research into sweeteners and appetite stimulation is inconsistent. Also, there is little evidence from longer-term studies to show that sweeteners lead to increased energy intake and contribute to the risk of obesity.

Polyols are a type of sugar-free carbohydrate generally manufactured from sugars and starches. The polyols licensed in the EU are:

• Xylitol E967
• Sorbitol E420
• Mannitol (E421)
• Isomalt (E953)
• Maltitol (E965)
• Lactitol (E966)
• Erythritol (E968)

Polyols are banned from soft drinks in the EU because of their laxative effect.

The truth about aspartame

Aspartame has been subject to more scare stories than any other sweetener, ranging from allergies and premature births to liver damage and cancer.

It is low calorie and up to 200 times sweeter than sugar. Aspartame is used all over the world as a sugar substitute in thousands of foods and drinks, including cereals, sugar-free chewing gum, low-calorie (diet) soft drinks and table-top sweeteners.

Aspartame has been extremely controversial since its approval for use by several European countries in the 1980s. A 1996 report suggested a link between aspartame and an increase in the number of diagnosed brain tumours. However, the study had very little scientific basis and later studies showed that aspartame was in fact safe to consume.

The European Ramazzini Foundation of Oncology and Environmental Sciences published several long-term studies in 2006 and 2007 linking the consumption of aspartame with an increase in cancers – namely lymphomas and leukaemias – in rats.

Following these studies, the US National Cancer Institute conducted a study of nearly half a million people, comparing those who consumed drinks containing aspartame with those who did not. Results of the 2006 study (PDF, 87kb) found aspartame did not increase the risk of leukaemia, lymphoma or brain cancer.

In 2013 the European Food Safety Authority (EFSA) conducted a comprehensive review of the evidence (PDF, 2.25Mb) and concluded that aspartame was safe for human consumption, including pregnant women and children.

In digestion, aspartame is quickly and completely broken down into by-products – including phenylalanine, aspartic acid and methanol – which then enter our system through normal routes. Hardly any aspartame enters the bloodstream.

However, the EFSA said the acceptable daily intake recommendations did not apply to people with phenylketonuria (PKU), a rare genetic disorder where the body cannot break down phenylalanine. People with this condition need to closely monitor their phenylalanine intake.

The EFSA report stated that, "PKU mothers with poorly controlled phenylalanine intake in their diet during pregnancy may give birth to babies with congenital heart diseases, microcephalus and impaired neurological function."

It is worth noting that phenylalanine occurs naturally in many protein-rich foods, such as milk, eggs and meat. Table-top sweeteners containing aspartame or aspartame-acesulfame K must be marked with "contains a source of phenylalanine".

Acceptable daily intake: 40mg per kg of body weight

Find out what the latest scientific evidence says about these other common artificial sweeteners:

• acesulfame K
• saccharin
• sucralose
• steviol glycosides (stevia plant extracts)
• sorbitol
• xylitol

Read The truth about sweeteners

Saccharin link to cancer discredited

Discovered in the US in 1879, saccharin is the oldest artificial sweetener.

It is calorie-free and 300 to 400 times sweeter than sugar. Some people find it has a bitter or metallic aftertaste.

A wide variety of foods and drinks have saccharin added to them, including baked goods, chewing gum and table top sweeteners.

Saccharin is also used in cosmetic products (such as toothpaste, mouthwash and lip gloss), as well as vitamins and medications.

Saccharin is not broken down when digested. It is slowly absorbed into the system and rapidly excreted, unchanged, by the kidneys.

After being suspected of causing bladder cancer in rats, the Canadian government banned saccharin as a food additive in 1977 (although restricted access to saccharin as a table top sweetener was maintained). The US government also warned that it could cause cancer.

Since then, many studies have disproved any link to cancer.

The European Scientific Committee for Food (SCF) re-evaluated the safety of saccharin in 1995 (PDF, 29kb) and concluded that it did not pose a cancer risk to people. It stated: "While it is unlikely that the tumours in the male rat bladder are of relevance for man, it has not been possible to unequivocally demonstrate this".

After a complete evaluation of the evidence in 1999 (PDF, 378kb), the International Agency for Research on Cancer (IARC) concluded that saccharin could no longer be considered a possible carcinogen in people.

Canada lifted the ban on saccharin in 2014. Some health groups maintain that infants, children and pregnant women should avoid it due to the possibility of having an allergic reaction, although there is no evidence to back this up.

Acceptable daily intake: 5mg/kg body weight.

Find out what the latest scientific evidence says about these other common artificial sweeteners:

• acesulfame K
• aspartame
• sorbitol
• sucralose
• steviol glycosides (stevia plant extracts)
• xylitol

Read: The truth about sweeteners

Sorbitol: helpful for diabetics?

Sorbitol is a low-calorie sweetener chemically extracted from glucose.

It is used as an alternative to sugar in a range of foods, including low-calorie and sugar-free foods, as well as pharmaceutical and oral health products, such as toothpaste and chewing gum.

Sorbitol has less of an effect on blood sugar levels than sugar, which can benefit people at risk of developing diabetes.

It has the look and feel of table sugar, but with 60% of sugar's sweetness and 30% fewer calories (2.6kcal/g, compared to 4kcal/g for sugar).

When eaten, sorbitol has a mouth-cooling sensation, with virtually no aftertaste. It also helps food stay moist, making it a useful ingredient in the production of confectionery, baked goods and chocolate.

Sorbitol is a polyol – a type of carbohydrate generally manufactured from sugar. Polyols are banned from soft drinks in the EU because of their laxative effect.

Sorbitol naturally occurs in certain foods, such as apples and pears; stoned fruit, such as peaches and apricots; and dried fruit, such as prunes and raisins.

When ingested, sorbitol is slowly and only partially absorbed in the intestine and converted into fructose in the liver. Too much sorbitol in the intestine can cause water retention, resulting in diarrhoea.

If consumed in large amounts, it can cause side effects such as bloating and gas. Unabsorbed sorbitol is broken down into carbon dioxide and then eliminated.

The EU's Scientific Committee on Food stated in a 1985 report that ingesting 50g a day of sorbitol causes diarrhoea. Foods that are made up of more than 10% sorbitol must carry a warning that excessive consumption may have a laxative effect.

A 2011 report by the European Food Safety Authority (EFSA) on the health claims of polyols, including sorbitol, concluded that they promote dental health by helping to neutralise plaque acidity on teeth and repairing tooth enamel.

The EFSA also accepted the claim that polyols have a lesser effect on blood sugar levels than sugar, due to their slow absorption rate. This could benefit people with impaired glucose tolerance, which is a risk factor for diabetes and cardiovascular disease.

The EFSA has not set an upper limit on daily intake of sorbitol, meaning there is no health risk from normal consumption levels.

Acceptable daily intake: none specified.

Find out what the latest scientific evidence says about these other common artificial sweeteners:

• acesulfame K
• aspartame
• saccharin
• sucralose
• steviol glycosides (stevia plant extracts)
• xylitol

For more information, read: The truth about sweeteners

How safe is sucralose?

Sucralose is a calorie-free artificial sweetener derived from sucrose and is up to 650 times sweeter than sugar.

Valued for having no bitter aftertaste, sucralose-based products are found in a broad range of lower-calorie foods, including table top sweeteners, fizzy drinks, chewing gum, baking mixes, breakfast cereals and salad dressings.

Because it is very sweet, sucralose is often mixed with other sweetening ingredients that are not calorie-free, such as dextrose or maltodextrin, to dilute its intense sweetness.

When consumed, most of the sucralose is not absorbed by the body and is eliminated through excretion. Between 8% and 20% enters the blood and is removed through urine, essentially unchanged. The EU's Scientific Committee on Food (SCF) has concluded that repeated consumption of sucralose is "unlikely" to lead to accumulation in the body (PDF, 128kb).

There have been reports of adverse reactions to sucralose, including claims that it could be a migraine trigger. There is also research suggesting that it could harm the immune system.

However, in a review of the evidence in 2000 (PDF, 128kb), the SCF concluded that sucralose is safe for human consumption. In particular, that it is not harmful to the immune system, does not cause cancer, infertility, pose a risk to pregnancy, or affect blood sugar levels.

Sucralose has no effect on tooth decay and is commonly found in oral health products, such as chewing gum. It also has less of an impact on blood glucose than sugar. Both of these health claims were validated in a 2011 review by the European Food Safety Authority (PDF, 331kb).

Acceptable daily intake: 15mg/kg body weight.

Find out what the latest scientific evidence says about these other common artificial sweeteners:

• acesulfame K
• aspartame
• saccharin
• sorbitol
• steviol glycosides (stevia plant extracts)
• xylitol

Read: The truth about sweeteners

Is xylitol good for your teeth?

Xylitol is a low-calorie sweetener obtained from a variety of plants.

It is added to a range of foods, medications and oral health products, such as toothpaste and chewing gum.

Chewing gum sweetened with xylitol promotes dental health by helping to neutralise plaque acidity on teeth and repairing tooth enamel.

It has the look and feel of table sugar and is just as sweet, but contains 30% fewer calories (2.4kcal/g, compared to 4kcal/g for sugar). When eaten, it has a mouth-cooling effect, with virtually no aftertaste.

Xylitol is a polyol – a type of carbohydrate generally manufactured from birch and other hardwood trees. Polyols are banned from soft drinks in the EU because of their laxative effect.

A variety of fruits and vegetables naturally contain xylitol, including plums, strawberries and cauliflower. Even the human body produces a small amount.

Xylitol is slowly and only partially absorbed in the intestine, and is converted into glucose in the liver. Too much xylitol in the intestine can cause water retention, which can result in diarrhoea. If consumed in large amounts, side effects can include bloating and gas. Unabsorbed xylitol is broken down into carbon dioxide and eliminated.

The EU's Scientific Committee on Food said in a 1985 report that ingesting 50g a day of xylitol can cause diarrhoea. Table top sweeteners containing xylitol must carry the warning: "excessive consumption may induce laxative effects".

In a 2011 review of xylitol’s health claims, the European Food Safety Authority (EFSA) accepted the claim that xylitol has a lesser effect on blood sugar levels than sugar, due to its slow absorption rate. This means it could help people with impaired glucose tolerance, which is a risk factor for diabetes and cardiovascular disease.

There have been claims that xylitol-sweetened chewing gum may help protect against middle ear infections (otitis media); however, the EFSA concluded that there was not enough evidence to support this claim.

The EFSA has not set an upper limit on daily intake of xylitol, meaning there is no health risk from normal consumption levels.

Acceptable daily intake: none specified

Find out what the latest scientific evidence says about these other common artificial sweeteners:

• acesulfame K
• aspartame
• sorbitol
• saccharin
• sucralose
• steviol glycosides (stevia plant extracts)

For more information, read: The truth about sweeteners

Are stevia plant extracts safe?

Stevia-based sweeteners use purified extracts from the leaves of the stevia plant, called steviol glycosides.

Marketed as a "natural sweetener", manufacturers hope steviol glycosides will appeal to consumers looking for a healthier alternative to sugar.

The plant extract – which is 200 to 300 times sweeter than sugar and is also calorie-free – has been used as a sweetener for many years in Asia and South America.

When used as a table-top sweetener, steviol glycosides are often mixed with other artificial sweeteners for texture and to mask their sometimes bitter aftertaste.

Steviol glycosides are approved for use in sugar-free soft drinks, hot beverages, jams, flavoured milk and other dairy products, cakes, desserts and alcohol, among other things.

When consumed, steviol glycosides are broken down into steviol, which is absorbed by the body. The body does not store steviol glycosides and they are rapidly eliminated in faeces and urine.

Steviol glycosides were approved by the EU in 2010 after the European Food Safety Authority (EFSA) carried out a comprehensive analysis (PDF, 532kb) of all the available evidence and concluded they were safe for human consumption.

Extensive research has been done on steviol glycosides, involving both humans and animals. After analysing all the available evidence, the EFSA's reviewing panel concluded that steviol glycosides are not carcinogenic or toxic and do not pose a risk to pregnancy or children.

Acceptable daily intake: 4mg/kg body weight

Find out what the latest scientific evidence says about these other common artificial sweeteners:

• acesulfame K
• aspartame
• saccharin
• sucralose
• sorbitol
• xylitol

Read The truth about sweeteners