Controlling Your Weight and PKU

Article 2 Controlling your weight

“I want to lose weight…”

The principles of losing weight for a person on a low protein diet are the same as for anyone else. It means taking in less energy (calories) than you burn off and increasing physical activity. It is important that you do not reduce your PKU supplement in order to lose weight as this will affect your Phe levels. Always take the amount of supplement recommended by your dietitian.

When losing weight, aim for a gradual loss of 0.5-1kg per week. Rapid weight loss or “crash dieting” may cause your blood Phe levels to rise as your body breaks down its protein stores. Crash dieting may also leave you feeling extra weak, tired, hungry and moody. Check with your doctor or dietitian about adjusting your diet to include appropriate foods and supplements. Specifically ask your dietitian about some of the lower calorie supplement options that are available to you.

Handy hint – What you eat on a day–to-day basis makes the biggest difference to your weight. Make small changes to your daily diet that you can stick to for long-lasting results! Occasional treats can be included in a sensible weight loss program, but the amount and frequency of these needs to be watched.

Common Questions

Check with your doctor or dietitian before making any changes to your diet.

  • How many meals should I have a day?
    • Eat three main meals daily and only 1 or 2 snacks daily, to avoid getting too hungry. Do not skip meals.
  • How many times should I take my PKU supplement per day?
    • It is usually 3-4 times evenly spaced over the day or as recommended by your doctor or dietitian.
  • What about the choice of my PKU supplement?
    • First, always take your PKU supplement as recommended by your healthcare professional. Ask their advice on low-calorie supplements. Different PKU supplement provide different amounts of calories based on the protein, fat and carbohydrate content. Check with your doctor or dietitian about which product is most appropriate for you.
    • Remember your PKU supplement provides you with the protein you need (without phenylalanine) and replaces the meat, chicken and fish that is included in non PKU weight reduction diets.
    • If you do not have your PKU supplement you risk feeling hungry and nibbling on extra foods as a result.

What about fat?

  • Limit high fat foods in your diet. Some tips to reduce fat in your diet include:
    • Use less oil, butter, margarine and salad dressings
    • Grill, steam, boil or bake foods without oil, butter and/or margarine
    • Keep fried foods (e.g. chips) to a minimum.
    • Watch the amount of low protein high energy snack foods like crisps, biscuits and cakes

What about sugar?

  • Decrease sugar in your diet. Keep high sugar foods and drinks to a minimum e.g. soft drinks, fruit juice, cakes and sweets.
  • Are there any special foods that will help me?
    • Lower fat food products (e.g. low-fat spread, low-fat mayonnaise) may be helpful if used in small amounts to replace higher calorie products. Check labels for protein content as usual and for aspartame artificial sweetener. The choice of protein supplement may also help in cutting your daily calories. Check with your doctor or dietitian on the most appropriate product.

Any ideas for snacks?

  • Fruit; raw free vegetables; 1-2 plain low protein biscuits; 1 slice low protein bread with thinly spread butter or low fat spread.

Daily Activity

Any activity uses up energy or ‘calories’. Daily activity can include everything from those that use very little energy such as sleeping to driving to watching TV, or using the computer to those that use much more energy such as being physically active , walking, running, cycling, gardening or playing sport or exercising. Your daily activity levels make difference to your weight as well as what you eat. This is because to keep a stable weight you need to burn as many calories as you are eating, but to lose weight you need to eat less than you burn.

Do you do enough ‘moderate’ activity?

Recommended guidelines say we should do at least 30 minutes of moderate physical activity daily. Examples include brisk walking, riding a bicycle, dancing or walking up stairs. This should be enough to raise your heart rate and leave you feeling slightly out of breath but not exhausted. A great and fun way to monitor your activity is to get a pedometer, which tracks your daily number of steps. You may set a goal of a certain number of steps per day, for example more than 10,000 and work on increasing this over time, or doing the same number of steps in less time (increasing the intensity). If you have not exercised for some time, or are over 40 years of age you should always get a health check with your doctor first before starting an exercise program.

The benefits of keeping active

It is much better to do a simple activity you can fit into your routine every day than “burn out” at the gym once a month. The many benefits of doing more activity include:

  • Increased energy levels
  • A feeling of general well being
  • Improved blood pressure
  • Better muscle tone
  • Protection against heart disease and some cancers
  • Sleeping better
  • Better mood

Check out our recipe section for some healthy meal and snack ideas!

“I want to gain weight…”

To put on weight you need to eat more energy (calories) each day than you burn off. High energy foods are rich in fat and sugar. Your doctor or dietitian will help you choose appropriate foods. It is still recommended that you exercise regularly unless your doctor has advised you otherwise.

Common Questions

Check with your doctor or dietitian before making any changes to your diet.

How many meals should I have a day?

At least 3 meals preferably with 2-3 additional snacks in between meals, throughout the day. If your appetite is small try to spread your food out over 6 small meals a day. Check with your dietitian about what is best for you.

How many times should I take my PKU supplement per day?

3-4 times evenly spaced over the day or as recommended by your doctor or dietitian.

What about the choice of my PKU supplement?

Always take your supplement as recommended by your healthcare professional. Different PKU supplements provide different amounts of calories based on the fat and carbohydrate content. Check with your dietitian about which product is most appropriate for you. A supplement that you enjoy and can take consistently is the most important factor in choosing one.

What abut low protein foods?

Eating larger portions of special low protein foods (e.g. our Loprofin food range) can help you gain weight without increasing your blood Phe levels.

What about fat?

In the Phe-restricted diet, food protein is limited. As a result of this, in order to get extra calories needed to gain weight you will have to increase either fat or carbohydrates. In this section we will talk about how to increase healthy fats in your diet. Oils such as canola, olive and vegetable are healthy choices for someone wanting to add extra calories. Butter and some margarines also provide extra calories, but should be used sparingly because of their high saturated fat content. Margarines containing oils such as canola and olive are less saturated and will be a better choice. Check the labels and look for margarines with mainly poly unsaturated or monounsaturated fats.

Suggestions for adding more calories from fat:

  • Add olive or canola oil to your low-protein pasta dishes
  • Spread margarine or butter on your low-protein bread or crackers
  • Add oil to sauces for vegetables
  • Add oils to your salad for great taste

What about sugar?

Another way to increase calories in the low protein diet is to increase the amount of sugar in it. Include more sugar, syrup, jam, honey, sweets, and sugary drinks e.g. 100% fruit juice. Another way is to use low-protein food products which contain both carbohydrates (as starches) and fat. It is important to speak with your dietitian about the best way to increase carbohydrates in the diet. Note: when adding sugars it is important to follow good dental hygiene.

Are there any energy supplements that will help me?

Your doctor or dietitian might recommend changing your protein supplement to one that provides more calories and adding an energy supplement such as Calogen to your diet.

What about snack ideas?

Try low-protein baking such as muffins, bread, biscuits or fruit, fruit smoothies, shakes and smoothies using your favourite low protein milk substitute e.g Milupa-LP-Drink.

Please Note: The dietary management for PKU varies for each person so all information presented here is for guidance only. Your own dietitian and/or doctor will advise you on all aspects relating to management of PKU for you and your family.”

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