Caffeine helps you lose weight, there’s no doubt about it. This is a relevant factor when we consider that caffeine is the most commonly consumed psychoactive drug in the world.

As with any drug, there are risks and rewards associated with consumption. And the effects can be short lived. From a cup of coffee (or many) to a pot of green tea, this post is going to delve into how to get the greatest health benefits from your caffeine. We’ll look at how achieve weight and fat loss with caffeine while avoiding the detrimental side effects.

By the time you’re done reading you’ll be an expert on how this stimulant effects the human system. What caffeine does in the body, why it works for weight loss and how to consume it responsibly.

What is Caffeine?

Caffeine is a central nervous system stimulant.

It’s used by millions of people worldwide on a daily basis to increase wakefulness, alleviate fatigue and improve concentration. It has mood-altering (psychotropic) attributes and is a mild diuretic.

Easy-Use Caffeine Guide: Download this health tool for keeping your caffeine intake at optimal levels for daily health and weight loss!

In the US, more than 90% of adults use caffeine regularly.

The people have spoken: low to moderate doses of caffeine are considered to be generally safe and provide a great number of health benefits, though excessive intake is a considerable health risk (especially in those with anxiety or heart disorders).

The FDA has determined 400 milligrams of caffeine – about 4-5 cups of coffee a day – to be a safe consumption level. Still, safe levels of caffeine consumption can result in:

  • Anxiety
  • Nervousness
  • Disrupted sleep
  • Dependency
  • Dehydration
  • Dizziness
  • Headaches
  • Uneven heart rate

Side Effects of Caffeine and Weight Gain

Caffeine increases the release of acid in your stomach, sometimes causing heartburn or an upset stomach. For those looking to lose weight, excess acidity is to be avoided, as acidity precedes cortisol release. The hormone cortisol causes the body to increase insulin release, impairs fat loss and generally predicts weight gains.

As a diuretic, caffeine will cause the body to purge water and thereby lose electrolytes like potassium and sodium. Caffeinated beverages do not typically cause dehydration, but caffeine pills can cause dehydration and incur vitamin deficiencies when not consumed with adequate water.

Heavy caffeine consumption should be avoided. More than 500-600 mg a day can lead to negative side effects:

  • Insomnia
  • Nervousness
  • Restlessness
  • Irritability
  • Diarrhea
  • Muscle Tremors
  • Nausea

Caffeine temporarily blocks a chemical called adenosine, a natural brain sedative, from being released. Thereby, you feel more awake for longer.

The effects of caffeine on sleep are largely determined by genetics, with most people falling somewhere between extreme sensitivity and near-total tolerance.

Healthy adults need around 8 undisturbed hours of sleep a night. Caffeine can interfere with both sleep and wake cycles, and sleep loss is cumulative. Through lost sleep, a heavy caffeine habit can lead to weight gain and fat retention resulting from cortisol increases in the system following sleep deprivation. Days after sleeplessness also show decreased impulse control, ie dietary discretion.

Consume with care.

How does Caffeine Work with Fat Loss?

Caffeine is absorbed into the blood and body tissues, reaching peak levels of concentration between 15-120 minutes after consumption.

As it stimulates the nervous system, caffeine tells the brain to break down fat cells. Caffeine also triggers the release of a hormone called epinephrine, which prompts the release of adrenaline. After these “fight or flight” chemicals make their way into the body, there’s increased demand to break down fat cells for use as energy.

Because it agitates the system in a controlled way, users see increased fat loss. A perfect time to make use of this stimulated nervous system is for exercise. Caffeine has been shown to increase overall athletic performance by 11-12% for the average user. Combing the revved-up feeling of a cup of coffee or green tea before a workout can really hammer away those fat deposits.


Your Resting Metabolic Rate (RMR) is the number of calories you burn while sedentary. A higher RMR means you’re less inclined to gain and keep weight.

Studies have shown caffeine to increase the metabolic rate between 3-11%, with larger doses (within reason) having a more pronounced effect.

This is theoretically due to the fact that caffeine increases your body temperature via thermogenesis and kicks your system into overdrive for a short time. What’s more, increases in metabolism were shown to signal an increase the burning of fat as well.

Caffeine won’t affect everyone’s metabolism the same. One study saw the increase in fat-burning rise as high as 29% – but only in lean people. Obese participants only saw an increased effect of 10%. The effects were also felt more strongly by young participants.


Easy-Use Caffeine Guide: Download this health tool for keeping your caffeine intake at optimal levels for daily health and weight loss!


Caffeine Tolerance and Weight Loss

Though it does boost metabolism in the short term, caffeine users develop a tolerance to the drug. This depletes effects it has upon fat burning and increasing metabolism.

For those intent upon resisting the buildup of a tolerance, cycling caffeine intake in bi-weekly intervals may prove effective. Taking two weeks on and two weeks off can be a challenge for habituated users, but may net a few extra calories here and there.

It is also theorized that the suppressive effects caffeine has upon appetite may reduce the desire to eat. While these claims are unsupported, the fact remains that tolerance will negate any such actions within the body.

Caffeine from Green Tea

Green tea is the ideal way to consume caffeine because it brings with a host of additional health benefits.

From a dietary perspective, green tea contains a variety antioxidant polyphenols like flavonoids and catechins. These chemicals serve to reduce the formation of degrading free radicals, while protecting cells from damage. Free radicals are famous for reducing the appearance of aging and blocking a host of viruses and other inflammatory diseases such as cancer and type 2 diabetes.

One cup of green tea contains around 40 mg of caffeine and is notorious for not causing the jittery effects of a cup of coffee.

Green tea contains the amino acid L-theanine, which increases the GABA neurotransmitter activity, effectively reducing anxiety while increasing the production of dopamine and soothing alpha waves in the brain.

Studies confirm a synergistic effect between caffeine and L-theanine as well, as both together work to combine brain function.

Caffeine itself has been shown to increase brain function, mood, reaction time, and memory. Combine these aspects with green tea’s many benefits for a super-drink.

Caffeine from Coffee

An 8 oz. cup of coffee contains between 50-135 mg of caffeine. The variability of caffeine in coffee can make it difficult to calculate total daily intake levels, especially if you love your cup o’ joe.

The rule is: the lighter the roast, the more caffeine.

Roasting coffee burns away caffeine, imparting that dark look and toasted flavor to the beans. For example, breakfast blends will have more caffeine than French Roast. A grande cup from Starbucks can contain well over 300 mg.

Studies show that while caffeine has short-lived effects upon fat loss and weight loss, coffee has measurably positive effects when it comes to preventing a wide variety of diseases:

Interestingly enough, 4-5 cups of coffee a day has been correlated with a longer lifespan. Whether from the metabolic or fat loss processes or not, people who stay constantly alert all day see a 12-16% variable increase in lifespan from coffee consumption. Another factor is that coffee is full of antioxidants, much like green tea.

Other Forms of Caffeine

Not many other forms of caffeine (besides matcha and yerba matte) can be recommended for fat and weight loss because they come with high doses of sugar and carbohydrates. Popular caffeine sources such as chocolate, energy drinks, sodas and caffeine pills are not healthful like tea and coffee.

While chocolate has been shown to have some positive benefits to health, sodas and energy drinks carry too much sugar and carbohydrates to be included in a healthy lifestyle. Caffeine pills and other weight loss supplements are suspect, as many are untested by the FDA and may contain ephedra, a dangerous stimulant banned by the FDA in 2004.

Easy-Use Caffeine Guide: Download this health tool for keeping your caffeine intake at optimal levels for daily health and weight loss!

Last Words

For those looking for a brief boost in their weight loss efforts, healthy sources of caffeine provide proven results. The stimulating qualities of caffeine make it a great complement to a workout routine, whether for the short or long term. Ultimately, a caffeine dependence will diminish the metabolic and fat loss potential for caffeine, but if you can balance and cycle your intake there may be an opportunity to preserve minor changes. Be sure to keep total consumption below 500 mg per day and apart from bedtime. Sleep loss will cause weight gain, so insomnia and restlessness from caffeine should be avoided. Choosing natural sources of caffeine, such as green tea and coffee, will provide additional benefits aside from those contained by the caffeine. Cheers to your health!


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