Ask the Expert: what is an unhealthy rate of weight loss?

03 January 2019

There are many important health benefits to losing weight; however it is important to ensure you do it in a healthy way. If your diet doesn’t include all of the essential nutrients your body needs, or is too extreme, then you could experience serious problems. Our Consultant Bariatric, Laparoscopic and Upper GI Surgeon, Mr Sanjay Agrawal, explains the right speed to lose weight, and how to know if it’s happening too fast.

What is a healthy rate of weight loss?

As a general rule, when losing excess weight using diet and exercise alone, you should aim to drop around 1-2 pounds per week. This is a healthy rate of weight loss, and it can be fairly easy to achieve. It shouldn’t require you to make dramatic changes to your diet or lifestyle, and therefore should be much easier to maintain your new healthy habits. If you have a lot of excess weight to lose however, you may be able to do it a little faster.

The more weight you have to lose, the faster you can lose it. If you’re obese then you may be able to lose more than 2 pounds a week without damaging your health, as long as you ensure your diet is balanced and you’re feeling well. It’s important to realise however, that the rate you’re losing weight at will slow down as you drop the pounds. It’s harder for your body to find stores of fat to use up as you lose weight, and as you’ll also be carrying less weight, and sustaining a smaller body, you won’t be using up as much energy.

How quickly could I lose weight with surgery?

If you have a large amount of extra weight, then weight loss surgery can help speed up dropping the pounds. The journey doesn’t end once the surgery is complete; you’ll get a lot of support to make sure you’re losing the weight in a healthy way too, and help sticking to your strict diet and exercise plan. The type of procedure you have, and how much you stick to your doctor’s advice, will impact the amount of weight you lose. For example, within the first year following your weight loss surgery, you can expect to lose on average:

  • Gastric band: 50% of your excess weight
  • Sleeve gastrectomy: 50-60% of your excess weight
  • Gastric bypass: 60-70% of your excess weight

The first six months following the surgery will be the fastest rate of weight loss, and you’ll continue to lose weight fairly quickly for the first year, and it will then slow down gradually. To ensure you’re making permanent changes, it’s important to persevere so that you can achieve your target weight, and then stick to it. Even with surgery, weight loss is a long process that requires patience and commitment.

Weight loss surgery isn’t a quick and easy option. Before your surgery even takes place, you’ll need to spend time speaking to your doctor, gaining dietary advice and preparing for the procedure. You’ll then have to commit to long term changes in your diet and lifestyle to make the surgery a success.

When is weight loss too fast?

If you notice any unusual symptoms then you should always seek help. If your weight loss is having a negative effect on your physical or mental health then you may be losing it too quickly. For example, if you:

  • Are too tired to do your usual activities
  • Feel faint, dizzy or light-headed
  • Are so irritable or upset that it’s interfering with your usual activities
  • Are losing hair or muscle
  • Have brittle fingernails, dry hair or skin problems
  • Notice your menstrual cycle has become irregular
  • Find it difficult to concentrate or complete your work
  • Are unable to think about anything other than weight loss

If you’re experiencing rapid weight loss and you haven’t improved your diet or getting more exercise, or you don’t know why you’re losing weight, you should see a doctor as I could be a sign of a serious health problem. Dehydration can also make you lose weight quickly, but the results aren’t long lasting and can be detrimental to your health, so make sure you’re drinking enough water.

How could I lose weight at a healthy rate?

To avoid damaging your health when losing weight, you’ll need to reduce the amount of calories in your diet without cutting out the essential nutrients your body needs to stay healthy. Nutritional supplements can help with this, and should be considered especially if you’ve had surgery such as a gastric bypass, as it can become more difficult for your body to absorb vitamins and minerals.

It’s also important to increase your activity levels, and not rely on dieting alone. Not only will exercise increase your metabolic rate and use up more calories, but it will also improve your health and strengthen your muscles and bones.

There are many factors that contribute to how much weight you will lose, including the weight you’re starting at and your metabolism, so it’s impossible to say which speed is best for everybody. However, if you’re exercising regularly, eating a balance diet, and you feel healthy whilst losing weight, then you’re probably doing it at a healthy rate. As much as weight loss can feel too slow or challenging at times, you will reach your goal as long as you persist.

If you would like more information on the different weight loss surgeries available, take a look at our News & Events page to see which free weight loss information and support group evenings we have coming up. Alternatively, if you would like to see Mr Agrawal for a private consultation, please call 0203 811 5089.

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