You've been eating less, moving more, and the scale is finally dropping. But something feels off — you look softer, feel weaker, and your energy is tanking. What's going on? Some of the weight you're losing may be muscle rather than fat.
This is a common and frustrating diet problem, and it can quietly affect people across Singapore and Malaysia who are cutting calories but not watching what they're losing.
When you slash calories, your body faces an energy shortfall. It doesn't draw only on fat stores. During a calorie deficit, the body tends to shift toward breaking down more protein, including muscle tissue, a process called muscle catabolism.
The result? You lose weight, but part of what you lose can be lean tissue rather than fat. How much depends on how big the deficit is, what you eat, and whether you exercise.
Muscle isn't just about appearance. It's the main contributor to your resting energy use. More muscle generally means a higher resting metabolism — your body burns more calories even while you're sitting at your desk or on the MRT. Losing muscle may lower that, which could be one reason some people hit a plateau or regain weight after dieting.
A slower metabolism may also make the next diet harder. Research on how repeated cycles of dieting affect lean mass is limited, so it's best to focus on protecting muscle during each attempt.
Some people on a calorie-restricted diet don't get enough protein. When protein intake is too low, the body lacks the building blocks — called amino acids — it needs to maintain muscle tissue, and more lean mass can be lost as a result.
This can be especially tricky in Singapore and Malaysia, where eating out two to three times daily at hawker centres or food courts is the norm. Rice-heavy meals, noodle dishes, and char kway teow tend to be carbohydrate-dominant. Protein portions — whether from fish, tofu, eggs, or meat — can be smaller than most people realise.
Some research suggests that higher protein intake during calorie restriction may help limit the loss of lean muscle mass compared to standard protein intake. The benefit appears modest, and results across studies are mixed.
This is the supplement category worth a closer look: protein supplements — specifically whey protein, casein protein, and plant-based protein powders.
They're not magic. They don't burn fat on their own. But they can help with a very real, very common problem: making it practical to reach adequate protein intake when your diet is calorie-restricted and your food choices don't always cooperate.
Whey protein is derived from milk and is one of the most researched supplements in sports nutrition. It's absorbed quickly, which is why it's often used after exercise. It's also rich in leucine — the amino acid most strongly linked to triggering muscle protein synthesis, which is the process of building and repairing muscle.
Think of leucine as an important "on switch" for muscle repair. Total protein intake and other amino acids matter too, so leucine is one signal among several.
Casein is also from milk but digests much more slowly. It releases amino acids steadily over several hours, which is why it's often taken before bed or during long gaps between meals. For anyone prone to late-night tze char suppers who's also trying to maintain muscle, casein taken before sleep may support muscle protein synthesis overnight. Most of this research was done in people doing resistance exercise, and evidence in people who are dieting is limited.
For those who are lactose intolerant, vegetarian, or prefer plant-based options, plant protein powders — typically pea or rice protein — are a reasonable option. Some research suggests that pea protein may be comparable to whey in supporting muscle thickness gains when combined with resistance training, although some analyses have ranked whey slightly higher.
Leucine deserves a special mention. It's a branched-chain amino acid (BCAA) that is a strong trigger for muscle protein synthesis. Some people supplement leucine specifically during periods of very low calorie intake or when they simply can't fit in a full protein serving.
It doesn't replace complete protein. Research on leucine taken on its own is limited and mixed, and it isn't clear that it helps maintain muscle during dieting.
Adequate protein intake may help limit muscle loss during dieting, but resistance exercise is the other half of the equation. Resistance exercise during weight loss appears to help hold on to muscle. Protein alone may not fully prevent muscle loss without it.
If you're desk-bound most of the day and only getting steps in on the commute, adding regular resistance sessions during the week may help. It doesn't have to be a gym — resistance bands, push-ups, and squats are all options.
This article is for general informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before starting any supplement or making significant dietary changes.
Ask Elaine how this applies to your goals and routine — free, no pressure.