Written by
Louise W Lu, PhD, MPH, BMLS
Written/Reviewed by
Alexandra V Goldberg, Registered Dietitian
Introduction
As “carb & fat blockers” become more popular, more women are using them as a handy helper for dinners out, social events, and even everyday meals. After all, they can, to some extent, reduce the absorption of sugars and fats, helping with weight and post‑meal glucose control.
These concerns aren’t unfounded. In nutrition science, some vitamins do rely on dietary fat for absorption—namely vitamins A, D, E, and K. But is the real‑world impact as worrying as it sounds? In this article, we’ll start from the underlying mechanisms and answer, point by point, how carb & fat blockers interact with nutrient absorption—so you can separate myths from facts.
Quick Navigation
1｜What Do Carb & Fat Blockers Actually Block?
Many people, when they first hear about “carb & fat blockers,” assume it means blocking all the nutrients from food. In fact, that’s not the case. What it really does is more like “giving your meal a discount”—the same bowl of rice or plate of food, but your body ends up absorbing less sugar and fat. This way, it helps reduce calorie burden and keeps blood sugar more stable.
Now let’s look at the natural ingredients in one capsule, how each works on carbs or fats, and how much less your body may absorb.
Step 1 - Blocking Carbs: Cutting Down the Calories from Rice & Noodles
Foods like rice, buns, and potatoes are essentially starch. Under normal conditions, enzymes quickly break starch down into glucose, which rushes into the bloodstream, spikes blood sugar, and triggers insulin—making it easy to store fat.
→ Equivalent to absorbing 5–8 g less starch (20–32 kcal).
Simpler view: A small bowl of rice has about 30 g carbs (≈120 kcal). With mulberry leaf extract, that’s like cutting away one-third of it.
→ Equivalent to 8–16 kcal.
Simpler view: Like spreading sugar release more evenly, so it’s used for energy instead of stored as fat.
Step 2 - Blocking Fat: Letting Some Oil Pass Through Instead of Being Stored
Fat is very calorie-dense—every 1 g of fat = 9 kcal. If nearly all the fat you eat gets absorbed, over time it easily leads to weight gain. Fat-blocking ingredients in this capsule work in the gut to intercept part of the fat and send it out of the body.
→ Equivalent to preventing 3–5 g of fat formation (27–45 kcal).
Simpler view: It doesn’t block fat directly, but makes it harder for sugar to become fat.
→ Equivalent to absorbing 2–3 g less fat (18–27 kcal).
Simpler view: Like tying oil to fiber and flushing it away.
→ Equivalent to absorbing 1–2 g less fat (9–18 kcal).
Simpler view: Like a magnet grabbing fat so it can’t enter the blood.
→ Equivalent to reducing 0.5–1 g fat conversion (4–9 kcal).
Overall Effect
- Block 7–12 g sugar (≈28–48 kcal)
- Block 3.5–6 g fat (≈32–54 kcal)
- Block new fat formation 3–5 g (≈27–45 kcal)
What Does This Mean in Everyday Food?
- Milk Tea (medium, full sugar ≈ 400 kcal) → One capsule ≈ blocks 1/4 cup milk tea
- Fried Chicken (one piece with skin ≈ 250 kcal) → One capsule ≈ blocks half a piece
- Potato Chips (70 g medium bag ≈ 350 kcal) → One capsule ≈ blocks 1/3 bag
- Rice (one bowl ≈ 120 kcal) → One capsule ≈ blocks 1/3 bowl
- Cooking Oil (one spoon ≈ 90 kcal) → One capsule ≈ blocks half a spoon
2｜How to Use a Carb & Fat Blocker
Understanding the principle behind carb & fat blocking is only the first step—more importantly, how to use it matters. If the method is off, the effect will be greatly reduced.
When should you take it?
How much should you take?
In general, 1–2 capsules before a main meal are sufficient. You don’t need it at every meal—use it mainly for gatherings, social occasions, or whenever you plan to eat high-sugar/high-fat foods.
Always pair with warm water
Warm water helps dietary fibre–type ingredients (e.g., enokitake extract, chitosan oligosaccharide) fully dissolve and expand, bind more effectively to sugars and fats, and enhance the blocking effect.
At the same time, warm water helps these ingredients form a gel-like matrix in the stomach, boosting satiety so you naturally eat less during the meal.
Compared with cold water, warm water is better tolerated by the GI tract and won’t overstimulate gut motility.
Think of it this way: like a dry sponge that only expands in warm water, allowing it to “soak up” more sugar and fat. If you don’t drink water, the “sponge” stays collapsed and the blocking effect drops.
Set the right mindset
Section 3｜Which Nutrients May Be Affected
Many people worry that while carb & fat blockers reduce sugar and fat absorption, they might also “block” other nutrients. The answer is: most nutrients are not affected, but a few may be influenced because they rely on fat for absorption.
Fat-Soluble Vitamins
Think of it this way: these vitamins are like “hitchhikers,” and fat is their “ride.” If there are fewer cars, their chances of catching a ride go down too.
Essential Fatty Acids
However, the impact is usually minimal, since the typical modern diet tends to include excess amounts of fat.
Trace Minerals
Additionally, taking a fish oil supplement before bedtime can compensate for potential Omega-3 loss.
