KUALA LUMPUR (Bernama) – In pursuit of their ideal body shape, many are now turning to liquid diets as a shortcut for weight loss. But how safe and effective is this weight-loss technique?
Liquid diets allow individuals to consume only liquid-based foods such as fruit and vegetable juices, smoothies, soups and protein drinks or supplements, making it easier for them to control their calorie intake and prevent overeating.
Dietitian Jazlina Syahrul from Universiti Putra Malaysia said while this diet can lead to significant weight loss and calorie deficits, long-term adherence may pose serious risks to both physical and mental health, especially if not properly planned or monitored by healthcare professionals.
She noted that inadequate protein intake can lead to muscle loss, causing the metabolic rate to decrease and making long-term weight loss more challenging.
“The lack of fibre in a liquid diet can also result in constipation and intestinal health problems. It may also increase the risk of deficiencies in essential vitamins and minerals such as iron and calcium. Prolonged calorie restriction can also lead to extreme fatigue, dizziness and reduced concentration,” she told Bernama.
For some people, a liquid diet can help establish healthier eating habits before transitioning to a more balanced diet. However, one of its biggest challenges is the lack of eating satisfaction as it does not provide the chewing sensation needed for psychological fulfillment and appetite control.
“Without professional supervision, an unbalanced liquid diet may lead to nutrient deficiencies, including protein, vitamins and minerals.
“This could also result in rapid weight regain once an individual returns to his or her regular diet,” she added.
Senior lecturer in dietetics at the Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Dr Shanthi Krishnasamy, also expressed concern over the abundance of meal replacement products on the market that have not been approved by the Ministry of Health Malaysia (MOH).
She said meal replacement products should provide the recommended nutritional balance, adding it is crucial to consult a doctor, dietitian or nutritionist before following this diet.
“From experience, this diet is not sustainable in the long run. Most individuals try it for a short period before stopping, leading to the ‘yo-yo’ effect where weight is lost and then regained,” she said.
Shanthi said liquid diets are usually prescribed as meal replacements for patients undergoing bariatric surgery, that is, for a two-week period where they are given liquid food five to six times a day before the procedure.
For sustainable weight loss, she recommended focusing on calorie reduction by controlling portion sizes; adopting a diet rich in fruits, vegetables and whole grains; and increasing physical activity.
“Although some may experience short-term weight loss, maintaining it in the long run can be difficult and may lead to metabolic issues.
“It is better to follow the (MOH’s healthy eating plate principle) ‘quarter-quarter-half’ concept, a simple method to properly portion meals and ensure all essential food groups are included in each serving,” she added.
Meanwhile, actress Sweet Qismina, who once followed a liquid diet to prepare for a movie role, does not recommend it, stressing that she followed it under medical supervision.
“The milk (prescribed for those on a liquid diet) is not something you can drink as you please. It is meant for patients who consume food through tubes, and it carries risks. I was able to consume it under a doctor’s advice.
“It is not a (healthy) way to lose weight; there are many better alternatives,” she said in a TikTok video, adding that the diet made her feel highly emotional due to food cravings.
