From the Guidelines
Yes, 700mg of caffeine can cause muscle twitching, as it exceeds the recommended safe limit of 400mg per day for healthy adults, and high doses of caffeine can overstimulate the nervous system, leading to muscle twitches, tremors, and spasms. According to a recent study 1, moderate coffee consumption, defined as three to five 8-oz servings per day or approximately 400mg caffeine per day, is considered safe and can be incorporated into healthy eating patterns. However, consuming 700mg of caffeine in one sitting is significantly higher than this recommended amount and can cause adverse effects.
The exact mechanisms by which caffeine causes muscle twitching are complex, but it is known to block adenosine receptors and increase the release of neurotransmitters like dopamine and norepinephrine, leading to hyperexcitability in the nervous system and muscles 1. Other symptoms that may occur with high caffeine intake include:
- Rapid heartbeat
- Anxiety
- Insomnia
- Digestive issues
- In severe cases, heart palpitations or even seizures
It is essential to reduce caffeine intake immediately if muscle twitching occurs and allow the body time to metabolize the caffeine, which typically takes 4-6 hours for half of it to be processed. Staying hydrated can help manage these symptoms, but if twitching is severe or accompanied by other concerning symptoms, it is crucial to seek medical attention. The European Food Safety Authority and other health organizations have established guidelines for safe caffeine consumption, and exceeding these limits can lead to serious health issues 1.
From the FDA Drug Label
Signs and symptoms reported in the literature after caffeine overdose in preterm infants include ... fine tremor of the extremities, hypertonia, opisthotonos, tonic-clonic movements,
- Muscle twitching can be considered related to the symptoms of fine tremor of the extremities and tonic-clonic movements.
- The provided dose of 700mg caffeine is significantly higher than the amounts associated with serious toxicity in the literature.
- Given the information, it is possible that 700mg of caffeine could cause muscle twitching due to the potential for inducing symptoms similar to those reported in cases of caffeine overdose. 2
From the Research
Caffeine and Muscle Twitching
- Caffeine can cause muscle twitching due to its effects on calcium transients and isometric force in muscles 3.
- Studies have shown that caffeine can potentiate twitch responses in both fast- and slow-twitch muscles, with the soleus muscle being more sensitive to caffeine's effects 3, 4.
- The threshold caffeine concentration for an observable increase in resting calcium levels was found to be 0.2 mmol l-1 for soleus muscles and 1.0 mmol l-1 for extensor digitorum longus muscles 3.
Caffeine Dosage and Muscle Twitching
- A dose of 700mg of caffeine is approximately equivalent to 10-12 mg/kg body weight for an average adult, which is within the range of doses used in studies that have reported increased muscle force and power output 5.
- However, high doses of caffeine (greater than 2 mmol l-1) have been shown to depress peak calcium levels in soleus muscles and prolong the rate of decay of the calcium transient, which could potentially lead to muscle twitching 3.
- The exact dosage at which caffeine causes muscle twitching is not well established, but it is likely that individual tolerance and sensitivity to caffeine play a significant role 5, 6.
Side Effects of Caffeine
- Caffeine ingestion has been reported to cause a range of side effects, including muscle twitching, jitteriness, and anxiety, particularly at high doses 5.
- The frequency and severity of these side effects can increase with higher doses of caffeine, and individual tolerance and sensitivity to caffeine can vary widely 5, 6.