What is it?
Although kidney disease can affect anyone, its leading causes are high blood pressure and diabetes.
Being overweight or obese can increase your chances of developing high blood pressure and Type 2 diabetes.
Obesity itself can also cause kidney disease, even in people without diabetes.
It can also increase the risk of heart disease, stroke and some cancers and seriously affect a person’s quality of life, self-esteem and emotional wellbeing.
Obesity levels are rising. It is predicted that half the UK population could be obese by 2050.
What are the causes
Obesity is generally caused by consuming more calories from food and drink than you burn off through physical activity. The excess energy is stored by the body as fat.
Obesity is an increasingly common problem because for many people modern living involves eating a lot of processed and convenience foods, which are often high in calories. People often eat more snacks in-between meals and have larger portions sizes, as well as spend a lot of time sitting down at desks, on sofas or in cars.
Symptoms
Common lupus symptoms include tiredness and fatigue, joint pains and skin rashes.
The commonest symptom of kidney disease in lupus is water retention, causing swelling of the face, limbs and abdomen. This is caused by leakages of protein in the urine (proteinuria) due to damaged glomeruli. If the protein leak is severe it may cause nephrotic syndrome.
Kidney damage may also be indicated by blood in urine (haematuria) and high blood pressure.
If kidney damage is well advanced, other symptoms including itching and muscle cramps, may also occur.
Diagnosis
A calculation called a Body Mass Index (BMI) is generally used to indicate whether a person is a healthy weight for their height.
For most adults, a BMI of:
- 18.5 to 24.9 means you're a healthy weight
- 25 to 29.9 means you're overweight
- 30 to 39.9 means you're obese
- 40 or above means you're severely obese
Sometimes very muscular people can have a high BMI so waist measurements are often used as an additional way to gauge excess fat.
Generally, men with a waist circumference of 94cm (37in) or more and women with a waist circumference of 80cm (about 31.5in) or more are more likely to develop obesity-related health problems.
Treatment
The best way to treat obesity is to:
- eat a healthy, reduced-calorie diet (as recommended by your GP or a dietitian) and
- exercise regularly – and try to do at least 30 minutes activity or exercise on at least five days per week. This could include brisk walking, swimming, or cycling. [A2]
- Some people may consider weight loss surgery as an option. But some forms of weight loss surgery can sometimes be complicated by a form of kidney disease called oxalate nephropathy.
Sticking to a diet and exercise plan on your own is really tough. So it can be really helpful to join a local weight loss group for support and encouragement, and exchange experiences and ideas with other people who are also aiming to lose weight and increase their fitness.
Help for you
It can be hard to lose weight successfully but setting yourself realistic goals, regularly monitoring your weight and receiving encouragement from family and friends can help you persevere.
Speak to your GP if you want help and advice about how to lose weight
You can also find practical tips – including a free 12-week NHS diet and exercise plan on the NHS website.
But always remember to speak to your kidney consultant or kidney dietitian before starting a diet plan or new exercise programme if you are on a restricted diet due to kidney disease.
Reviewed April 2019
The need for research
We need more research on how to help prevent and treat obesity. We also need research into how obesity appears to cause kidney disease, and into how best to prevent oxalate nephropathy amongst patients who have had some types of bariatric surgery.
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