The Claim

Long-term fasting in healthy adults is associated with a significant reduction in serum sodium levels (p < 0.01) and an increase in serum calcium levels (p < 0.05), which is associated with prolonged QTc interval (p < 0.05) indicating altered electrolyte homeostasis and potential risk for cardiac arrhythmias.

Source: Effects of long-term fasting and confinement on the cardiovascular activity

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
37score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Correlation
1 study reviewed
In plain English

In healthy adults, prolonged fasting is linked to lower blood sodium, higher blood calcium, and a longer QTc interval on heart monitors, which are physiological changes associated with increased risk of irregular heart rhythms.

See the scientific wording

Long-term fasting in healthy adults is associated with a significant reduction in serum sodium levels (p < 0.01) and an increase in serum calcium levels (p < 0.05), which may indicate altered electrolyte homeostasis and potential risk for cardiac arrhythmias due to prolonged QTc interval prolongation (p < 0.05).

Why this might work

When a person fasts for a long time, sodium levels in the blood drop and calcium levels rise. This imbalance disrupts the flow of electric charges in heart muscle cells, making it harder for the cells to reset after each beat. As a result, the heart takes longer to recover between beats, which shows up as a longer QTc interval on an ECG and increases the chance of dangerous irregular heart rhythms.

Verified mechanismbased on 1 study

What the research says

1 study

  1. Study: Effects of long-term fasting and confinement on the cardiovascular activity

    This study found that when healthy people fast for a long time, their blood sodium goes down, calcium goes up, and their heart takes longer to reset between beats—which can make irregular heartbeats more likely. So yes, long fasting can mess with heart rhythm.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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