It’s World Kidney Day this month (11 March), so we thought we would use the opportunity to write about the kidneys and what you can do to keep yours strong and healthy.

Situated at the lower back, the two “kidney-shaped” organs work tirelessly, filtering blood. Simply put, the kidneys remove substances the body doesn’t need or want from the blood. Those are then excreted in the urine. The acidity of the blood, which only has very narrow limits, is kept constant by the kidneys. In addition, the kidneys produce hormones that are involved in blood formation or the regulation of blood pressure. Calcitriol, a hormone need for the last step in converting vitamin D into its active form, is also produced in the kidneys.

When kidney function is impaired, fluids and waste products can no longer be fully excreted. For a long time, those affected do not notice, but after a while, symptoms, such as water retention in the legs or feet, or persistently puffy eyes, may appear. Other symptoms can be fatigue, dry and itchy skin, frequent urination – especially at night, foamy urine or blood in the urine. If the kidneys fail, the only option is blood purification (dialysis) or a kidney transplant. Chronic kidney disease is the most common kidney problem caused by high blood pressure in most cases. Kidney stones are also widespread.

Whether the kidneys are working well can be determined by looking at relevant blood values. Creatinine and urea are particularly important, but so are several other factors. The examination of the urine also helps doctors to check kidney function. If you regularly get a full blood count done, blood values referring to kidney function are usually included. However, please make sure you see your doctor and request a test if you experience symptoms.

How to keep your kidneys shipshape

The best you can do for your kidneys is avoiding risk factors. The two main conditions posing a risk for kidney disease are high blood pressure and diabetes. Patients suffering from metabolic syndrome (the combination of obesity, high cholesterol, diabetes and hypertension) have an increased risk of both heart and kidney disease. With this in mind, you can put a strategy for the protection of your kidneys together.

1. Lose excess body fat

If you are overweight or obese, you already know many reasons to lose weight, and here’s another one. Losing weight may help prevent or even reverse diabetes and lower blood pressure – and your kidneys will thank you for it. The fatty tissue in the abdominal cavity produces inflammatory hormones that additionally endanger the kidneys. You have probably tried to shed pounds before, perhaps with limited or short-lived success. Yet, it can be done. If you haven’t been successful yet that’s not your fault. Obesity is a disease that has less to do with willpower and a lot to do with hormone signalling. With the right dietary advice, based on up-to-date research and professional coaching, it is possible to successfully lose weight. If you would like to learn more, please give us a call, and we’ll have a chat.

2. Eat real food

Phosphate binds to calcium, which gradually hardens the blood vessels’ inner walls, increasing the risk for heart attack and stroke. Phosphates can also accelerate the ageing of skin and muscles and the chance for osteoporosis.

Natural phosphate is found in many foods, such as wholegrain bread, meat, egg yolks, dairy products, mushrooms, pulses or nuts. In principle, phosphate is found in everything that contains protein. A little phosphate is vital. The mineral serves the body as an energy carrier and is involved in certain processes in cell metabolism. Muscles need phosphate to function.

Too much phosphate, however, is detrimental. The body absorbs only 50 per cent of phosphates from plant foods and 70 per cent from animal protein. Healthy kidneys can cope with this. Artificially added phosphates, however, are usually freely soluble and absorbed completely. With the increasing consumption of fast food and other highly processed convenience foods, the body is virtually flooded with phosphates. In the past three decades, phosphate intake has doubled.

3. Drink up

Kidney Research UK  recommends staying hydrated and drinking plain water as it may even protect the kidneys. That makes sense, as plain water is the only drink we actually evolved to drink. Drinking helps the kidneys clear sodium, urea and other waste products. It keeps the kidneys flushed, making kidney stones less likely to develop.

But how much is enough? The NHS recommends eight 200ml glasses of water for women, ten for men. In the US, the advice is “8×8” (eight times eight ounces) of water. Either result in an intake of approx. 2 litres per day. If you stopped random people in the street and asked them how much water a person needs to drink each day, most would probably give the correct answer. Surprisingly, there have been few scientific studies to determine the most effective amount – that said, the advice seems about right. However, if you tend to develop kidney stones, you may need to drink a little more, approx. 2.5 to 3 litres per day.

Kidney Research UK advises going by the colour of your urine. It should be straw coloured. If it is darker, you need to drink more until your urine gets lighter. On average, we should be visiting the toilet 5-7 per day to urinate. If you go less frequently, you may be dehydrated.

Another drinking-related piece of advice that is persistent yet outdated is that tea and coffee do not count towards your fluid intake or even dehydrate you. This is because they contain caffeine which has a mild diuretic effect. However, you would have to drink vast amounts or very strong coffee for this to affect your water balance.

Water is still the best drink for humans. If you do not like the taste, you can infuse water with fruit, such as orange, lemon or berries, or give it a refreshing note with cucumber, mint or ginger.

Fizzy drinks, especially cola, are not recommended. In the case of most soft drinks, the high fructose content (a sugar found in table sugar and fruit) disqualifies them and high consumption may, in fact, be harmful for the kidneys. This is because the liver breaks down fructose and produces uric acid as a by-product of this process. High amounts of sugar can overwhelm the system, leading to high uric acid levels, potentially resulting in kidney stones and gout. About 10% of kidney stones are uric acid stones.

The artificial sweeteners of diet drinks are thought to affect the gut microbiome, which plays an important role in our immune protection, including its ability to fight urinary tract infections. Cola in particular should be consumed in moderation – not only does it contain a lot of sugar or artificial sweeteners, but it is also a source of phosphate.

4. Hold the green smoothie

Many healthy foods – whole grains, fruit, vegetables, pulses, nuts and seeds – contain a compound called oxalic acid or oxalate. 75% of kidney stones consist of oxalates. Examples of foods with high levels include chocolate, beetroot, peanuts, rhubarb, sweet potatoes, spinach, and Swiss chard. Limiting the intake of these foods may be beneficial for people who form calcium oxalate stones.

To reduce the risk of forming oxalate stones, eat and drink calcium foods such as milk, yoghurt, and some cheese alongside oxalate-rich foods. Oxalate and calcium from food are more likely to bind to one another in the stomach and intestines before entering the kidneys. This makes it less likely that kidney stones will form. A diet low in calcium increases your chances of developing kidney stones.

5. Limit salt

Adding excessive amounts of salt to food can be detrimental to kidney health. This is because sodium (salt) causes the kidneys to lower our calcium levels and excrete calcium in the urine. A high sodium diet therefore can increase the likelihood of developing another stone. Tinned or ultra-processed foods, as well as fast food and takeaways, are common sources of hidden sodium. You can lower your sodium intake by choosing fresh low-sodium foods to reduce calcium leakage in the urine.

6. Look After Your Gums

Gum disease, known as periodontitis, is strongly associated with kidney disease. Dentist have found that those people with the worse inflammation of the gums have the worse kidney function. Dental hygiene, such as brushing, flossing and regular dentist visits,  is vitally important for kidney health. Increasing your daily intake of fruit and vegetables (aim for 2 fruit and 5 vegetables a day) helps to ensure that you get plenty of vitamin C and potassium, both of which play a part in keeping gums healthy.

As you can see, there is a lot that you can do to help (or hinder) the kidney’s job. Maintaining a healthy body weight, staying active, keeping hydrated and following a real food diet goes a long way to support your kidneys.

For more information about our services and webinars, please contact Lisa or Emily at info@vitalhealthnutrition.co.uk