The app that helps you manage your kidney disease and diet.

Protein can be found in both animal and plant-based sources. Protein content and completeness differ across various foods – foods from animal sources such as meat, poultry, fish and eggs are good sources of complete protein (comprises all essential amino acids), whereas plant-based foods such as vegetables, nuts and seeds are incomplete protein sources (lacking one or more essential amino acids).

Some examples of protein content in commonly consumed foods:

• 1 matchbox-sized portion of chicken, fish, or meat provides 7-10g of protein

• 1 whole egg provides about 8g of protein

• ½ cup of cooked beans or lentils provides 10g of protein

Usually, it is said that 1 matchbox-sized portion of meat (7-10g protein) provides 1 protein exchange. Hence, if your protein requirement is 50g per day, you will require approximately 5-6 protein exchanges per day.

Do consume a variety of protein foods from different sources, to ensure you get a complimentary intake of the different amino acids, especially if you are a vegetarian or prefer to opt for plant-based protein foods.

What are protein foods?

Protein can be found in foods from animal sources, such as poultry, red meat, fish, seafood, eggs and dairy products (e.g. milk, yoghurt and cheese). Some plant-based foods such as soy milk, tofu, tempeh, nuts, beans and legumes are also good sources of protein.

There are 2 types of protein: complete and incomplete protein. Protein is made up of amino acids and there are a total of 20 different amino acids that our body requires. However, 11 out of the 20 amino acids can be produced by our body while the remaining 9 are the essential amino acids that can only be obtained through dietary sources. Thus, complete proteins are those which contain all the 9 essential amino acids our body requires. On the other hand, incomplete proteins contain some, but not all, of the essential amino acids. Complete proteins are generally from animal sources such as fish, poultry, beef, eggs. Among plant-based sources, soy is a complete protein, while other plant-based sources such as legumes, nuts, seeds and vegetables are incomplete proteins.

If you are vegetarian or prefer plant-based foods, you can still obtain adequate and good quality protein, by combining a variety of different food sources to ensure you are getting all the different amino acids and sufficient protein needed.

Including a variety of protein foods in your daily diet is also important because many protein sources include high levels of vitamins and minerals such as iron, vitamin B, zinc, and omega 3 fatty acids.

Depending on which stage of CKD you are in, whether you are undergoing dialysis treatment, and your current body weight, your protein requirements might vary.

How do I calculate my protein requirement?

Typically, an amount of food containing about 7-10g of protein is classified as 1 protein exchange. Some examples of 1 protein exchange equivalents include:

• 1 matchbox-sized portion of chicken, fish, or meat

• 4 medium-sized prawns

• 1 whole egg, or 2 egg whites

• ¼ block of tofu

• ½ cup of cooked beans or lentils

• 1/3 cup of nuts

If you are not required to restrict your protein intake, you would need to consume about 1g or protein per kg of body weight. For instance, if you weigh 60kg, you will require about 6 protein exchanges each day. In order to consume 6 protein exchanges a day, you can aim to achieve 3 exchanges each at lunch and dinner. Alternatively, if you choose to have an egg at breakfast (1 exchange), you can have about 2 to 3 exchanges at lunch (e.g. ¼ block of tofu with ½ cup of cooked beans) and another 3 exchanges at dinner (e.g. 3 matchbox-sized portions of meat).

However, if you are on protein restriction (e.g. at CKD stage 4)., then you may only take 0.6g of protein per kg of body weight. For instance, if you weigh 70kg and your daily protein intake is recommended at only 42g per day, this means you should only consume about four protein exchanges per day. Four protein exchanges may comprise of 1 whole egg (1 protein exchange), ¼ block tofu (1 protein exchange), and 2 matchbox-sized portions of meat or fish (2 protein exchanges).

References

Potassium is an essential mineral commonly found in many foods and supplements, especially in fruits and vegetables. It is also an electrolyte which aids in our daily body functions such as regulating blood pressure, maintaining fluid balance, aiding muscles contraction and nerve functioning, as well as regulating heart rhythms.

As our body does not produce potassium, it is essential to obtain adequate amounts of potassium from our diet. Potassium levels in our body can be affected by a variety of factors, such as diarrhoea, vomiting, kidney disease and usage of medications or supplements.

Potassium is an essential mineral commonly found in many foods and supplements, especially in fruits and vegetables. It is also an electrolyte which aids in our daily body functions such as regulating blood pressure, maintaining fluid balance, aiding muscles contraction and nerve functioning, as well as regulating heart rhythms.

As our body does not produce potassium, it is essential to obtain adequate amounts of potassium from our diet. Potassium levels in our body can be affected by a variety of factors, such as diarrhoea, vomiting, kidney disease and usage of medications or supplements.

At the early stages of kidney disease, your kidneys may still be able to remove excess potassium. However, if your condition progress, you may need to restrict your potassium intake because your kidneys are unable to remove excess potassium efficiently. When potassium in your body builds up and your blood potassium levels are too high, this results in weakness, nausea, and tachycardia (irregular, fast heartbeats).

You are encouraged to aim for between 2,000 – 3,000mg of potassium content per day *. If your blood potassium levels are too high (hyperkalaemia), you should try to opt for lower potassium foods where possible. If you tend to have too low blood potassium levels (hypokalaemia), you may include some of the higher potassium foods in your daily diet instead.

To maintain your blood potassium levels within the recommended range, it is essential to be mindful of the amount of potassium you consume throughout the day. Here are some ways to manage your blood potassium levels when cooking at home or eat out:

When cooking and eating at home:

• Soak vegetables in water to allow some potassium to be “leached” out to reduce the potassium content. Nonetheless, vegetables with a higher potassium content should not be consumed frequently.

• Discard the liquids from canned fruits and vegetables

• Limit intake of soups with vegetables and herbs that have been prepared over long cooking times, as more potassium may have leached into the liquids

• Even though low sodium foods are better alternatives in general, salt substitutes tend to contain higher levels of potassium chloride content. Be wary of the food labels when using lower-sodium food products.

When eating out:

• For Western cuisines, choose salads instead of potato-based sides like fries, chips, or mashed potato, as potato is higher in potassium

• Avoid deli and processed meats, as they are higher in potassium and sodium. Opt for a plain salad and pasta with non-tomato-based sauce instead (e.g. aglio olio pasta)

• For Chinese cuisine, choose vegetable dishes that are lower in potassium (e.g. bean sprouts or cabbage instead of spinach)

• Try to avoid vegetable-based soups and broths, and limit dishes or desserts with chocolate and nuts.

Whether eating at home or dining out, do remember that portion sizes are crucial in managing your potassium intake. Consuming large portions of low-potassium foods can lead to a high potassium intake as well. Aim for moderation and balance, such as having smaller portions of foods higher in potassium, balanced with regular portions of foods lower in potassium.

References

Potassium is widely found in fruits and vegetables; however, some are much higher in potassium content than others. Root vegetables and tubers (potatoes, pumpkin, yam etc), tomato, beans and lentils have higher potassium content. Fruits such as avocado, banana, oranges, kiwi, and juices also contain higher potassium levels. Another fruit to be cautious of is the starfruit. With CKD, it is best to completely avoid starfruit as it contains a neurotoxin which the kidneys are unable to excrete from the body, and may result in side effects such as hiccups, mental confusion, and seizures. Other foods which also have higher potassium content are wholegrains and bran, dairy products, and nut products.

Foods that are lower in potassium include berries (blueberries, cranberries, strawberries, raspberries) and vegetables such as carrot, corn, and cucumber. For carbohydrate foods such as rice, noodles, pasta and bread, refined (“white”) carbohydrates are lower in potassium compared to their wholemeal counterparts.

If your blood potassium level is within the ideal range, it is still encouraged to exercise moderation when consuming foods that contain potassium. This is because, for certain foods, you may tend to consume more than one typical serving. For instance, 1 small apple is considered low in potassium. However, if you were to consume a large apple or two small apples, the potassium content is increased and contributes a greater proportion to your daily potassium intake.

Many food labels might not state or declare the amount of potassium in the food, so it is important to keep a watchful eye. Potassium can also be hidden in foods such as dried fruits, salt substitutes, chocolate, and preserved foods (as they might contain potassium additives). Some of the foods with the highest additives are breaded products, processed meat, soft drinks, and ready-to-eat foods.

If you are unsure about which foods are lower or higher in potassium, click on the link below for an overview of some common foods

Figuring out potassium

Phosphorous is one of the most abundant minerals in our bodies. Together with calcium and vitamin D, phosphorus helps to form and keep our bones and teeth healthy. It is also needed to help our bodies produce energy, and works with B vitamins to keep our blood vessels and muscles working.

Phosphorus is an essential nutrient that is present naturally in most foods such as protein-rich foods and dairy products. It is also available as an approved ingredient added during food processing.

At the early stages of kidney disease, your kidneys may still be able to remove excess phosphorus. However, with Stage 5 or dialysis, phosphorus may be accumulating in your body, which may in turn cause weakness in your bones, and increase the risk of vascular calcification and heart disease. At that stage, you may feel that it is a challenge keeping your blood phosphorus level within the range recommended by your doctor.

Your doctor may prescribe you with phosphate binders, which are medications that reduce your body from absorbing phosphorus from the foods you eat. This is to prevent a build-up of phosphorus in your blood which may lead to weak and brittle bones, increasing the risk of breakage. Take them as suggested by your doctor in order to keep your phosphorus level within the recommended range.

Did you know that protein foods such as meat, fish, poultry and milk are also rich in phosphorus? Although protein foods contain significant amounts of phosphorus, you are advised not to avoid protein foods completely. It is important to eat enough protein as recommended by your doctor or dietitian, to maintain your normal body functions and prevent malnourishment.

If your blood phosphorus level increases progressively or is persistently high, and you have been advised by your doctor or dietitian to lower your blood phosphorus level to within the recommended range, you may then need to limit your intake of phosphorus. Here are some tips to help you manage your phosphorus intake:

• Choose fresh foods instead of processed foods. Fresh foods such as meat, fish, poultry, fruits and vegetables generally have higher nutritional value compared to processed foods. While organic phosphorous occurs naturally in fresh foods, it is not as readily absorbed by our body compared to inorganic phosphorus added to processed foods.

• Choose fresh foods lower in phosphorus. Fresh protein-rich foods are naturally contain organic phosphorus. Choose protein-rich foods lower in organic phosphorus such as fish, lean meat, lean poultry and egg whites. You may want to avoid offals, nuts, egg yolks and fish with edible bones (such as anchovies and sardines), as they contain more organic phosphorus than other protein-rich foods. You could also include some plant proteins (e.g. beans and soy) in your diet, as plant-based phosphorus is less readily absorbed compared to phosphorus from animal sources.

• Choose processed foods without added phosphorus. When grocery shopping, read food labels and choose products without “phosphorus” or “PHOS” (e.g. phosphoric acid, pyrophosphates, polyphosphates and dicalcium phosphate) in the ingredients list. This may help to eliminate the majority of phosphorus additives from your meals.

• Choose the right cooking methods. When cooking at home, preparing meat and poultry using methods such as soaking, blanching and boiling may remove up to 50% of the organic phosphorous, provided the water or soup is discarded or not consumed.

• Choose wisely when eating out. When eating out, choose dishes that do not include ingredients higher in phosphorous (e.g. choose pasta tossed with olive oil and garlic instead of cream-based pasta, roast chicken instead of grilled sausages etc). Pair up your meal with fresh fruits and vegetables which have low phosphorus content, and drink only a sip of soda or avoid chocolate desserts.

  Here are some examples of what can be included as part of your kidney-friendly diet with a reduced phosphorus intake:

  Figuring out phosphorus

  References

What is sodium?

Sodium is a type of mineral that can be found in many foods, naturally or as an added ingredient.

In our body, sodium has several important functions:

• Regulates fluid and electrolyte balance

• Regulates blood pressure

• Conducts nerve impulses

• Influences muscles to contract and relax

How to manage my sodium intake?

While sodium is important for your body to function normally, excessive consumption can increase blood pressure and in turn lead to CKD progression.

In the early stages of CKD stage 1-2, the damage to your kidneys is generally mild and your kidneys are still able to function well enough to remove excess sodium. But you should still control the amount of sodium you consume daily to better manage your blood pressure and delay the progression of CKD. As a rule of thumb, aim to keep to 2,300mg of sodium per day.

Other than sodium chloride, known as table salt, sodium can also be found in:

• Commercial condiments and seasonings such as sauces, gravy mix/granules, bouillon or stock cubes, liquid stock, ready-made pastes, ketchup, flavoured salts (i.e garlic, onion salt)

• Processed foods such as cold-cuts, sausages, cheese, canned foods, preserved foods (i.e salted fish, anchovies), smoked/cured foods, instant noodles, canned/instant soups, savoury snacks and pastries, microwaveable or ready-to-eat meals, fast-food

• Sports or isotonic drinks, packaged vegetable juice

  Tips to reduce sodium when cooking at home:

• Plan to have most of your meals home-cooked instead of eating out frequently

• Use fresh ingredients such as fresh fish, poultry, meat, vegetables, and fruits

• If using frozen fish, meats, poultry or vegetables, choose those that are not crumbed or breaded

• Use fresh ingredients and aromatics (e.g. lemon, lime, chilli, ginger, onion, garlic, mushrooms, curry leaves, tomatoes etc) to naturally enhance the flavour of dishes instead of adding excessive salt

• Use herbs and spices (e.g. pepper, cilantro, mint leaves, basil, turmeric etc) to enhance the aroma and flavours of dishes instead of adding excessive salt

• Make your own soup stocks and gravies using fresh ingredients instead of using commercially-prepared stock, canned soups, or instant gravies

• When grocery shopping, look out for labels such as “unsalted”, “no added salt”, “reduced sodium”, “lower in sodium”, “low-sodium”, “low in salt”

• Read the Nutrition Information Panel and compare the sodium content between different products (per 100g/100ml) to choose the lower sodium option

  Tips to reduce sodium intake when eating out:

• Avoid finishing soups, gravies or sauces as these tend to be high in sodium

• Opt to leave out the gravy and sauces, or ask for them to be served separately to avoid finishing them

• Avoid dipping your foods in additional sauces and condiments (e.g soy sauce, Hoisin sauce, ketchup, chilli sauce)

• Have a taste of your food before you add more salt or seasoning, as the dish may already be tasty without the need to add more

• Opt for dishes with mostly fresh ingredients instead of processed foods such as fish balls, luncheon meat, sausages or preserved items (e.g salted eggs, preserved vegetables, salted fish etc.)

  Tips to reduce sodium intake when eating out:

• Avoid finishing soups, gravies or sauces as these tend to be high in sodium

• Opt to leave out the gravy and sauces, or ask for them to be served separately to avoid finishing them

• Avoid dipping your foods in additional sauces and condiments (e.g soy sauce, Hoisin sauce, ketchup, chilli sauce)

• Have a taste of your food before you add more salt or seasoning, as the dish may already be tasty without the need to add more

• Opt for dishes with mostly fresh ingredients instead of processed foods such as fish balls, luncheon meat, sausages or preserved items (e.g salted eggs, preserved vegetables, salted fish etc.)

  75% of sodium consumed comes from salt, sauces and seasonings added when preparing food.

  20% comes from processed food such as lunchen meat, instant noodles, fish balls and savoury snacks

  5% comes from naturally occurring, sources such as meats and seafood

  References

Fats play important roles in our body. They are stored in our body as an energy source, they provide protection to our vital organs by cushioning them, and they provide a medium for fat-soluble nutrients to transported around our body. Not all fats are unhealthy, and moderate amounts of fats should still be included in your diet. Nevertheless, it is important to remember that fats provide more calories per gram, compared to other nutrients such as protein and carbohydrates. If high-fat foods are consumed in excess, this can lead to weight gain and obesity.

Cholesterol is a waxy, fat-like substance present in the blood. Our liver produces cholesterol, but it can also be found in animal sources such as egg yolks, seafood (e.g prawns, crabs, oysters, roe), organs, and animal fat. Our body needs cholesterol as a building block and to maintain the structure of cell membranes, as well as to make Vitamin D, hormones and bile acids.

Two types of cholesterol are transported throughout our body:

• LDL (low-density lipoprotein) cholesterol, or sometimes known as the “bad” cholesterol. Most of our body’s cholesterol is made up of this type of cholesterol.

• HDL (high-density lipoprotein) cholesterol, or sometimes known as the “good” cholesterol because it helps to pick up cholesterol in the blood and transport it back to the liver, where cholesterol is removed from our body.

Cholesterol levels in your body can be detected through a blood test. High levels of LDL-cholesterol could lead to a build-up of cholesterol in the walls of your blood vessels, forming plaque and narrowing your blood vessels, thereby increasing your risk of heart disease and stroke. In contrast, higher levels of HDL-cholesterol have been associated with a lower risk of cardiovascular diseases such as heart disease and stroke.

Triglycerides are another type of fat that our body makes from food that we eat. Hight levels of triglycerides in the blood also increases the risk of cardiovascular disease.

Four types of dietary fats that can be categorised into healthy and unhealthy fats.

Unhealthy fats

• Saturated fat. This type of fat increases LDL-cholesterol. It is found mostly in animal fats and skin, lard, full-fat or full-cream dairy, butter, ghee, palm and coconut oil, non-dairy creamer and cocoa butter

• Trans fat. This type of fat increases LDL-cholesterol and decreases HDL-cholesterol. It is found mostly in fried foods and high-fat snacks (e.g donuts, fritters, potato chips), baked goods (e.g buns, pastries, biscuits, cookies), oils that have undergone processing to become solid at room temperature (e.g shortening)

Healthy fats

• Polyunsaturated fats. These include omega-3 fats that help to lower the risk of heart disease by reducing blood clotting in blood vessels, protecting arteries from hardening, and reducing triglyceride levels. Omega-3 fats can be found in oily fish such as salmon, sardine, longtail shad and Spanish mackerel, as well as plant-based foods such as walnuts, canola oil and soybean oil, flaxseeds. They can also be found in products fortified with omega-3, such as eggs or bread.

  Another type of polyunsaturated fat is omega-6 fats that help in lowering total and LDL-cholesterol levels in the blood. Omega-6 fats can be found in foods such as plant-based oils (e.g. corn oil, soybean oil, sunflower oil) and seeds (e.g. sunflower seeds, sesame seeds).

• Monounsaturated fats. This type of fat helps to reduce total and LDL-cholesterol levels in the body. Monounsaturated fats can be found in avocado, plant-based oils (e.g. olive oil, canola oil, peanut oil) and nuts (e.g. almonds, cashew nuts, hazelnuts).

While high blood cholesterol levels are a known contributor to heart disease, CKD itself is also a risk factor for heart disease so it is even more important to keep your kidneys healthy post-transplantation.

In general, 25-30% of our total calorie intake should come from fats. For example, if you are on a 2000kcal diet, that works out to about 55 to 66g of fats a day. Even when you include fats as part of your diet, remember to choose healthier polyunsaturated or monounsaturated fats instead of saturated or trans fats.

References

Sources of fluids

Fluids refer to any food or beverage in liquid form. Common beverages in our diet includes water, coffee, tea, milk, creamers, evaporated milk, fruit or vegetable juices, smoothies, soft drinks, cordials, syrups and alcohol. In addition, anything that melts into liquids also contribute to your fluid intake. Examples of such foods include ice cubes/chips, ice cream, sorbets/sherbets and popsicles.

Foods that contain liquids such as soups, gravies, sauces, porridge, yoghurt, puddings, gelatin and jelly also contribute to your daily fluid intake.

Some fruits and vegetables naturally contain fluids as well. However, these are usually not counted towards your daily fluid intake and you can still include fruits and vegetables as part of a balanced diet if taken in the recommended portions.

Water

Water is essential since your body comprises 50-70% of water. Each cell, tissue and organ in your body needs water to function well, hence your body needs water to survive.

Water is needed for functions such as:

• Regulating your body temperature

• Lubricating and cushioning joints

• Removing wastes from your body through urine, sweat and defecation

• Maintaining blood volume and carrying oxygen and nutrients to your cells

Furthermore, severe dehydration can lead to kidney damage or acute kidney injury (AKI). Some studies show that even mild but frequent dehydration can also lead to kidney damage.

As one of your kidneys’ functions is to regulate fluid balance, blood passes through your kidneys where it is filtered and excess water is removed then excreted through urine. At the early stages of CKD (stages 1-2), your kidneys are generally mildly impaired and are still able to function well enough to remove wastes and excess fluids. You are less likely to notice symptoms of fluid retention such as swelling in your face, arms, or legs or shortness of breath due to fluid build-up in your lungs at this stage.

Tips to manage fluid intakeIn the early stages of CKD (1-2), there is generally no definitive restriction on how much fluids you should consume daily. While it is generally advisable for you to drink at least 6 to 8 glasses of water per day, other factors such as health, pregnancy, breastfeeding, physical activity level or hot and humid weather may require increased fluid intake. However, at later stages of CKD (3 and above, dialysis), you may be required to limit your fluid intake to prevent fluid retention. It is best to speak with your doctor or dietitian to get a better understanding of your fluid requirements.

When it comes to beverages, water is a practical and reliable way to keep yourself hydrated. It is also naturally low in calories, sugar and fats compared to other beverages that are higher in sugar and/or fat. Consuming such beverages frequently can increase your risk of Type 2 Diabetes or contribute to high blood sugar levels in diabetics and/or result in weight gain, all of which can accelerate CKD progression.

If you struggle with drinking plain water, you can try to meet your fluid requirements by:

• Adding fruits such as strawberries, blueberries, a slice of orange/lemon, a squeeze of lime, or mint leaves to plain water to add some flavour

• Choosing water to quench your thirst while having your meals and snacks

• Bringing a water bottle around with you or keeping a cup of water at your desk, to increase your water intake as compared to other types of beverages

• Adding frozen fruit cubes to plain water

• Drinking tea (e.g. green tea, Oolong tea, red tea etc) or fruit teas, prepared from tea bags or loose leaves without adding sugar

If you are required to restrict your fluid intake:

• Use a measuring jug/cup or mark your cup/jug with measurements. You can consume your drinks from or pour in drinks into the measuring jug/cup to keep track of how much fluids you are consuming daily

• Manage thirst by sucking on ice cubes or chips,sugar-free hard candies, lemon slices or frozen fruits (e.g blueberries, grapes) instead of gulping down drinks

• Limit your intake of sodium as it not only causes you to feel more thirsty but excess sodium also holds on to water in your body

• If you are on dialysis, your healthcare providers may adjust the amount of fluids to be drawn out during dialysis

  References