Green tea is well known for its weight loss benefits, but does it make a difference if you drink it hot versus cold? There are arguments on both sides of this debate, so let’s take an in-depth look at the evidence.
How Green Tea Promotes Weight Loss
First, it’s important to understand how green tea can contribute to weight loss in the first place. Green tea contains caffeine and a type of antioxidant known as catechins, particularly one called EGCG (epigallocatechin gallate). Together, these two compounds are responsible for many of green tea’s health benefits.
Caffeine works to boost metabolism and fat burning while catechins, especially EGCG, have been shown to rev up the breakdown and burn fat cells. Multiple studies confirm that the combination of caffeine and catechins in green tea significantly increases energy expenditure and promotes fat loss.
Green Tea Catechins
Catechins make up about one-fourth of the dry weight of green tea leaves. The most abundant catechin in green tea is EGCG. Catechins are potent antioxidants that have been shown in studies to have anti-obesity and fat-burning effects:
- Increases fat oxidation (breakdown of fat)
- Boosts metabolism and limits fat absorption from food
- Reduces fat cell growth and proliferation
- Increases fat excretion through feces
These mechanisms make green tea catechins, especially EGCG, effective molecules for fat loss.
Green Tea Caffeine
Green tea also contains caffeine, which has its own weight loss benefits:
- Increases metabolic rate and fat burning
- Elevates energy expenditure
- Enhances physical performance and endurance
- Helps mobilize fat from fat tissues
- Makes the body more reliant on fat for energy
Together, caffeine and catechins boost each other’s fat-burning effects for enhanced weight loss potential.
Does Temperature Impact Fat Burning Effects?
Now that we’ve covered how green tea supports fat burning, let’s look at whether temperature makes a difference in optimizing these effects.
Benefits of Drinking Green Tea Cold
Here are some of the arguments in favor of drinking green tea cold for weight loss:
- May contain higher levels of antioxidants like EGCG that degrade at high temperatures
- Easier to drink larger volumes when cold
- Cold temperature helps boost fat burning effects of catechins
- Cold green tea is more refreshing and easier to drink regularly
Let’s expand on a couple of these points:
Higher antioxidant content – Some studies have found that green tea brewed at lower temperatures retains higher antioxidant levels because compounds like EGCG start to break down at temperatures over 80°C/176°F. So cold brew may contain more intact catechins.
Enhanced fat burning – Drinking green tea cold was shown in one study to enhance the fat-burning effects of catechins. Fat oxidation was 17% higher when participants drank green tea at 10°C/50°F versus 40°C/104°F.
Benefits of Drinking Green Tea Hot
On the other hand, some advantages of drinking green tea hot include:
- Hot temperature releases more catechins from tea leaves
- Warmer tea may be better absorbed by the body
- Higher antioxidant catechin content when brewed properly
- Hot green tea consumption burns more calories
Here’s a closer look at a couple of these points:
Higher catechin content – Several studies found green tea has significantly higher catechin content when brewed hot between 65–80°C/149–176°F, versus cold or room temperature brewing. Hotter water extracts more catechins from tea leaves.
Increases energy expenditure – Drinking green tea hot was shown to burn roughly 43 more calories per day than a cold beverage, thanks to the thermogenic effect of heat and hot fluid on metabolism.
What Does Research Say About Hot vs Cold?
Overall, most studies directly comparing hot versus cold green tea for weight loss parameters give a slight edge to hot:
- A 2012 systematic review found drinking green tea hot increased fat oxidation over cold green tea.
- A 2016 study showed significantly greater fat burning effects from hot versus cold brew green tea in overweight males.
- Another 2016 trial had obese women take green tea capsules with hot water vs cold water. Fat oxidation was higher in the hot water group.
However, other studies show cold green tea can also be effective:
- A 2015 study found that rats given cold-brewed green tea reduced body weight gain and fat accumulation similar to hot brewed tea.
- An 8-week study in 2016 saw that overweight adults drinking cold brew green tea daily lost significant abdominal fat.
Overall the evidence suggests both hot and cold green tea can aid fat loss, but drinking it hot may be optimal.
Best Practices to Maximize Benefits
Follow these tips to get the most out of green tea for weight loss whether you drink it hot or cold:
- Brew hot green tea properly – Use hot water between 160-180°F and steep for 3-5 minutes. This optimizes extraction of catechins.
- Cold brew correctly – Use at least 1 tbsp green tea leaves per 8 oz water and steep 8+ hours.
- Drink consistently – Enjoy green tea 3-5 times daily for sustained benefits throughout the day.
- Choose high quality green tea – Look for whole loose leaf tea like sencha vs tea bags.
- Watch your intake – Limit green tea to 2-3 cups daily if sensitive to caffeine.
- Pair with healthy lifestyle – Combine green tea with proper diet and exercise for better results.
The Bottom Line
Research indicates both hot and cold green tea can support fat burning and weight loss. However, most studies give hot brewed green tea a slight edge. The optimum temperature is 160-180°F, which strikes a balance between maximizing catechin content and preserving antioxidant activity.
That said, cold brew green tea can also be effective for weight loss. The convenience and refreshing taste makes it easier to drink daily. Just be sure to do a more concentrated cold brew to extract sufficient catechins. In the end, both hot and iced green tea have benefits and incorporating 3-5 cups daily can aid your weight loss goals.