This World Diabetes Day, and every other day, it's important that just because diabetes is a hidden condition, it doesn't get ignored.

More than 4.9 million people in the UK have diabetes, while 13.6 million are at an increased risk of type 2, according to Diabetes UK.

So, whether you suspect you might have the condition, have been recently diagnosed, are supporting someone else with it or just want to learn more, here's what you need to know.

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What is diabetes?

Diabetes is a lifelong condition that causes a person's blood glucose levels (also called blood sugar) to become too high, according to the NHS. There are two main types, type 1 and type 2, though some can also get gestational diabetes.

Pre-diabetes is when people have blood glucose levels above the normal range, but are not high enough to be diagnosed with the condition itself. But it's important to keep in mind that if your levels are higher than most, your risk of developing full-scale diabetes is increased.

Getting diabetes diagnosed early on is key to prevent it getting progressively worse, which can happen if left untreated.

What is type 1 diabetes?

Type 1 diabetes is where the body's immune system attacks and destroys the cells that produce insulin. You need to take insulin every day to keep your blood glucose levels under control. Type 1 is not linked with age, being overweight or lifestyle factors, whereas type 2 is.

Type 1 symptoms

The NHS website says you should see a GP if you have symptoms of type 1, which include:

• feeling very thirsty

• peeing more than usual, particularly at night

• feeling very tired

• losing weight without trying

• thrush that keeps coming back

• blurred vision

• cuts and grazes that are not healing

• fruity-smelling breath

Type 1 signs and symptoms can come on quickly, particularly in children.

Type 1 diagnosis

To get tested, your GP will do a urine test and might also check your blood glucose level. If they suspect you have diabetes, you'll be advised to go to hospital immediately for further assessments, where you will stay until you get results (usually the same day).

If you are diagnosed, then a specialist diabetes nurse will explain everything you need to know about the condition, including how to manage it, test your own blood glucose and how to inject insulin.

Finger-prick tests have long been used to manage diabetes, though you can now check your glucose levels at any time with a continuous glucose monitor (CGM) or flash monitor.

This involves using a sensor, a small device you attach to your arm or tummy that senses how much glucose is in the 'interstitial' fluid under your skin, and a reader or receiver, which shows the results (you can also read them on your smartphone). Some types have optional alarms to alert you if your levels go too low or high.

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While interstitial fluid readings have made many people living with diabetes' lives much easier, it's important to remember they're a few minutes behind your blood glucose levels. This means you'll still need to do finger-prick checks every now and then, particularly when you drive or have a hypoglycaemia (when your blood glucose level is too low), as this tells you what your level is at that moment.

Although being diagnosed with and managing diabetes can be difficult at times, you can still do the things you enjoy. This useful NHS guide on being newly diagnosed provides information to help, including how to recognise and treat a hypo, useful websites, online courses and more.

What is type 2 diabetes?

Type 2 diabetes is where the body does not produce enough insulin, or the body's cells do not react to insulin. It is far more common than type 1, with around 90% of all adults in the UK with diabetes living with it.

It can be linked to being overweight or inactive, or having a family history of type 2 diabetes. You're also more at risk of this type of diabetes if you're over 40 (or 25 for south Asian people), have a close relative with diabetes, are overweight or obese, are of Asian, African-Caribbean or black African heritage.

Many people can have type 2 diabetes without realising, because symptoms don't always make you feel unwell.

Type 2 symptoms

The NHS website says you should see a GP if you have symptoms of type 2 (similar to type 1), which include:

• peeing more than usual, particularly at night

• feeling thirsty all the time

• feeling very tired

• losing weight without trying to

• itching around your penis or vagina, or repeatedly getting thrush

• cuts or wounds taking longer to heal

• blurred vision

Type 2 diagnosis

You should also see a GP straight away if you're worried you may have a higher risk of getting type 2, who will ask you about your symptoms. You check your risk here.

Type 2 diabetes is usually diagnosed by blood or urine tests or something else, with results usually taking one to two days to come back.

If you have the condition, your GP will explain the results, what to expect next and the treatment they recommend. They'll typically talk to you about what the condition is, how high blood sugar can impact your health, if you need to take medicine, your diet and exercise, lifestyle factors like drinking and smoking.

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Gestational diabetes

Gestational diabetes can also occur during pregnancy, when some women have such high levels of blood glucose that their body is unable to produce enough insulin to absorb it all.

While it can happen at any stage of pregnancy, it is more common in the second or third trimester. It usually disappears after giving birth.

That said, it can cause problems for you and your baby during pregnancy and after birth, but the risks can be reduced if the condition is detected early and well managed.

Causes of diabetes

Elaborating on the above, the amount of sugar in the blood is controlled by a hormone called insulin, which is produced by the pancreas (a gland behind the stomach), the NHS explains.

Normally, when food is digested and enters your bloodstream, insulin moves glucose out of the blood and into cells, where it's broken down to produce energy.

However, if you have diabetes, your body is unable to break down glucose into energy because there's either not enough insulin to move it, or the insulin produced doesn't work properly.

While there are no lifestyle changes you can make to lower your risk of of type 1 diabetes, you can help manage type 2 diabetes through healthy eating, regular exercise and achieving a healthy body weight.

There's nothing you can't eat if you have type 2 diabetes, but the NHS suggests limiting certain foods. You should eat a wide range of food (fruit, veg and some starchy foods like pasta), keep sugar, fat and salt to a minimum, and make sure you eat breakfast, lunch and dinner every day – do not skip meals.

If you need to change your diet, it might be easier to make small changes every week, it adds.

Reducing the risk of type 2 diabetes with lifestyle

Diet, exercise and a healthy lifestyle can also help to reduce the likelihood of getting type 2 diabetes, with more than 13.6 million people in the UK at an increased risk.

"Fortunately – even in people with a strong family history of diabetes – making positive lifestyle choices can help avoid diabetes altogether," says Dr Sundhya Raman, medical doctor and lifestyle medicine physician, Plant Based Health Professionals.

In terms of diet, Raman says we should try to avoid "processed foods, sugar-sweetened foods and drinks, saturated fats (found in animal source foods and tropical oils), and red and processed meats".

On exercise, she explains it is never too late to start, and build up gradually. "Most people think they need to be quite fit before they get a benefit from exercising, but in fact going from doing nothing to doing something is when the biggest gains are achieved."

It seems sleep is very important too. "We should all be aiming for 7-8 hours of sleep a night, and people who chronically sleep less than this amount raise their risk of diabetes by about 30%," she says.

"When we don’t get enough sleep we also have dysregulated levels of our hunger and satiety hormones so are more likely to eat more, particularly foods that are not good for us and make us put on weight, so sleep should also be a priority."

Of all lifestyle factors, Raman says poor diet is the biggest risk. "In studies, the dietary group who have the lowest rates of diabetes are wholefood plant-based.

They are also the group that tend to have the lowest BMI compared with any other dietary group such as pescatarians or omnivores, and we know that a high BMI is one of the most significant risk factors [for having diabetes].

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Plant-based diet

Plant-based diets can reduce the risk of type 2 diabetes by up to 60%, according to Plant Based Health Professionals. But how does this work?

Soluble fibre, she explains helps us to feel full and maintain a healthy weight, release the carbohydrate from our food into our bloodstream slowly, and is the superfood for bugs that live in our colon, of which a healthy balance of can lower the risk of diabetes.

"Plant foods are also full of antioxidants that help reduce the damage that happens to our cells from everyday activities, as well as some of the more damaging things we do such as eating the wrong kinds of foods or sitting for prolonged periods," Raman adds. "We also know that some of the compounds in plant foods switch on genes that optimise our metabolism.

She also says wholegrains are the food type that have been shown in studies to be particularly important in reducing diabetes and cardiovascular risk. However, in the UK we don't have specific guidelines on how many portions to eat, or any legislation on what can be termed a wholegrain, so people can eat processed foods with few wholegrains, thinking they are improving their health, or think they're bad for people with diabetes, as are often grouped under carbs.

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"I would recommend three portions of wholegrains per day, ideally as unprocessed as possible." She also recommends a variety of fruit and vegetables, as well as variety in your nuts, seeds, wholegrains, lentils, legumes, herbs and spices, while prioritising plant sources of proteins over those from animal sources.

In some cases, plant-based are also effective at reversing type 2 diabetes, reversing insulin resistance, which is thought to happen when fat gets stored in our muscle and liver, and damages cells."One of the ways in which a whole-food plant-based diet is incredibly beneficial is that people tend to lose weight when they follow this dietary pattern, and we know that weight loss can reverse diabetes."

Make sure you consult a doctor before making any big dietary changes.

For more information, visit the NHS' website on diabetes, or seek support from Diabetes UK on 0345123 2399.

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