Podcasts > Stuff You Should Know > Short Stuff: Feed A Cold, Starve a Fever

Short Stuff: Feed A Cold, Starve a Fever

By iHeartPodcasts

On the Stuff You Should Know podcast, Josh Clark and Chuck Bryant tackle the age-old advice, "Feed a cold, starve a fever." First, they trace the origins of this saying, revealing its 16th-century roots and widespread popularity by the mid-19th century.

However, the hosts then explain how modern medical experts overwhelmingly advise against this practice. They discuss a 2002 Dutch study demonstrating how fasting can significantly impair the immune system's response. In contrast, nourishing the body supports immune function and recovery from illness. Through their analysis, Clark and Bryant make a compelling case for discarding this outdated adage.

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Short Stuff: Feed A Cold, Starve a Fever

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Short Stuff: Feed A Cold, Starve a Fever

1-Page Summary

The Origins of "Feed a Cold, Starve a Fever"

This advice first emerged in the 16th century, when John Whithalls stated that "fasting is a great remedy of fever," per Josh Clark. The full phrase arose in the mid-18th century, gaining popularity by the 1850s.

Modern Medical Consensus: Poor Advice

Today's experts overwhelmingly agree this advice is ill-advised and potentially harmful. Chuck Bryant explains forcing food when sick can disrupt digestion, while starving a fever deprives the body of nutrients and fluids vital for recovery.

2002 Study on Fasting's Effects

As Bryant notes, a Dutch study found fasting for 24 hours led to an 83% drop in the key immune protein [restricted term] gamma. Conversely, a meal replacement increased [restricted term] levels, boosting the immune response. The study also observed rises in interleukin-4 levels with fasting, suggesting fasting alters immune defenses unpredictably.

1-Page Summary

Additional Materials

Clarifications

  • The Dutch study from 2002 found that fasting for 24 hours led to a significant decrease in the immune protein [restricted term] gamma. This protein plays a crucial role in the body's immune response. The study also showed that meal replacement increased [restricted term] levels, which can boost immune function. Additionally, fasting was observed to impact interleukin-4 levels, suggesting that fasting can unpredictably alter immune defenses.
  • [restricted term] gamma and interleukin-4 are proteins involved in the immune system's response to infections and diseases. [restricted term] gamma helps regulate the immune response against viruses, while interleukin-4 plays a role in allergic reactions and fighting parasites. These proteins are crucial for coordinating the body's defense mechanisms and maintaining overall health. Changes in their levels can impact how effectively the immune system functions during illness or when the body is under stress.
  • Fasting can impact immune proteins like [restricted term] gamma, which play a crucial role in the body's defense mechanisms. A study found that fasting for 24 hours significantly reduced [restricted term] gamma levels, potentially weakening the immune response. Conversely, consuming a meal replacement increased [restricted term] levels, suggesting that proper nutrition can support immune function. Additionally, fasting was observed to influence interleukin-4 levels, indicating that fasting can have unpredictable effects on immune defenses.

Counterarguments

  • While modern medical experts generally advise against the "feed a cold, starve a fever" approach, some alternative medicine practitioners might argue that there are individual cases where modified fasting or specific diets can support the body's healing process, depending on the illness and the patient's overall health.
  • The advice to avoid forcing food when sick might be too general, as some illnesses may not significantly disrupt digestion, and eating could provide necessary energy for the immune system to function effectively.
  • The Dutch study's findings on fasting leading to a drop in [restricted term] gamma and an increase in interleukin-4 levels might not be universally applicable, as immune responses can vary greatly among individuals, and other factors such as the type of illness, the duration of fasting, and the individual's nutritional status could influence the results.
  • The study's observation that a meal replacement increased [restricted term] levels suggests that the quality and type of food consumed during illness might be more important than simply eating or fasting, indicating a need for more nuanced dietary recommendations during sickness.
  • The historical context of the phrase "feed a cold, starve a fever" might have been based on observations and experiences that predate modern scientific understanding, and while not recommended today, it could have been a reflection of the best knowledge available at the time.

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Short Stuff: Feed A Cold, Starve a Fever

The history and origins of the "feed a cold, starve a fever" advice

The saying "feed a cold, starve a fever" has been a common piece of health advice for many years, with its roots dating back centuries.

The phrase "feed a cold, starve a fever" has been around since the 18th century, but its origins can be traced back to the 16th century

The concept of "starving a fever" can be traced back to the 16th century, specifically to the year 1574. Josh Clark references a dictionary from that time compiled by John Whithalls, which included the statement "fasting is a great remedy of fever," representing the origins of the "starve a fever" portion of the saying. This belief held that withholding food could potentially help in managing a fever by reducing the body's need for energy.

The full phrase, including the "feed a cold" part, emerged in the mid-18th century, with references to it found in the 1850s

As for the complete advice as we know ...

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The history and origins of the "feed a cold, starve a fever" advice

Additional Materials

Clarifications

  • John Whithalls was a figure from the 16th century who compiled a dictionary that included the statement about fasting being a remedy for fever. This statement is one of the early documented instances of the concept of "starving a fever." Whithalls' work provides historical evidence of the belief that withholding food could help manage fevers by reducing the body's energy needs. His contribution adds to the understanding of the origins of the advice to "starve a fever."
  • Fasting in the context of managing a fever was believed to reduce the body's energy needs, potentially aiding in fever management by lessening the demand on the body's resources. This historical belief suggested that withholding food during a fever could help the body focus on fighting the illness rather than digesting food, allowing the body to direct its resources towards combating the fever. The idea was rooted in the notion that fasting could support the body's natural healing processes during times of illness, particularly when dealing with fevers. This practice was based on the belief that abstaining from food could assist the body in its efforts to overcome the fever by conserving energy and resources for the immune response.
  • The saying "feed a cold, starve a fever" originated in the 18th century, but it wasn't until the 1850s that the full phrase gained popularity and became more widely recognized in health advice. During this time, the concept of feeding a cold and starving a fever became more established and commonly ref ...

Counterarguments

  • The advice "feed a cold, starve a fever" is not supported by modern medical science, and following it could potentially be harmful.
  • The origins of the phrase may be historically interesting, but they do not validate the advice from a medical standpoint.
  • The belief that withholding food during a fever reduces the body's need for energy is overly simplistic and does not take into account the body's complex needs during illness.
  • Modern medicine suggests that proper nutrition and hydration are important for recovery from both colds and fevers.
  • The popularity of the saying may be attributed to cultural transmission rather than evid ...

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Short Stuff: Feed A Cold, Starve a Fever

The current medical consensus on this advice, and why it is considered poor advice

Modern medical experts overwhelmingly agree that the "feed a cold, starve a fever" advice is ill-advised and potentially harmful

Medical experts today widely regard the old adage "feed a cold, starve a fever" as outdated and even harmful.

When suffering from a cold, forcing oneself to eat when not hungry can be counterproductive

If you have a cold, you may not feel very hungry. Medical advice suggests that it's best not to force yourself to eat. Eating large amounts when lacking an appetite can be counterproductive because your body may not be primed to digest food efficiently while unwell.

Starving a fever is especially problematic

Conversely, the advice to "starve a fever" is considered especially problematic. When fighting a fever, your body requires adequate nutrition and hydration. Fasting when feverish can deprive the body of the necessary nutrients and calories it needs to combat the infection.

Depriving the body of needed calories and fluids when suffering from a fever can further weaken the immune system and delay recovery

Forcing yourself to eat while sick can be unhelpful, but it's crucial that you don't entirely for ...

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The current medical consensus on this advice, and why it is considered poor advice

Additional Materials

Clarifications

  • When you have a cold, your body's priority is fighting off the virus, not digesting food. Eating when not hungry can divert energy away from the immune response. This can make you feel more fatigued and hinder your body's ability to recover efficiently.
  • The advice to "starve a fever" is considered problematic because when the body is fighting a fever, it requires adequate nutrition and hydration to combat the infection effectively. Fasting when feverish can deprive the body of essential nutrients and calories needed for recovery, potentially weakening the immune system and prolonging the illness. It's crucial to maintain nourishment and hydration during a fever to support the body's immune response and aid in a quicker recovery process.
  • Fasting when feverish can deprive the body of necessary nutrients and calories because the body's metabolic rate increases during a fever, requiring more energy. Without adequate nutrition, the body may not have the essential resources to support the immune system in fighting off the infection. Depriving the body of nutrients during a fever can weaken the immune response and hinder the body's ability to recover efficiently. It's important to provide the body with sufficient nutrients and calories during illness to support the immune system and aid in the recovery process.
  • Depriving the body of essential calori ...

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Short Stuff: Feed A Cold, Starve a Fever

The scientific evidence on how eating and fasting affect the immune system when sick

A study by Dutch researchers in 2002 explored the relationship between food intake, fasting, and the immune system. Their findings suggest that fasting and eating can have opposite effects on our body's immune response when sick.

A 2002 study by Dutch researchers found that fasting for 24 hours led to a significant decrease in levels of the immune protein [restricted term] gamma

The research indicated that individuals who fasted for 24 hours experienced a sharp decline in their immune system's capabilities. Specifically, there was an approximate 83% reduction in levels of [restricted term] gamma, which is a crucial immune protein involved in the body's targeted immune response against pathogens. The implication from this part of the study was clear: fasting may weaken the immune system's ability to respond to illnesses.

In contrast, the same study found that providing participants with a meal replacement drink led to a sharp increase in [restricted term] gamma levels

On the flip side, the study observed that a group which consumed a meal replacement showed a marked increase in [restricted term] gamma levels after fasting. This indicates that instead of fasting, consuming calories and nutrients can have a beneficial impact on certain aspects of the immune response at a time when the body is fighting an infection or other illness.

The study also observed increases in levels of the immun ...

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The scientific evidence on how eating and fasting affect the immune system when sick

Additional Materials

Clarifications

  • [restricted term] gamma is a protein crucial for the immune system's response against pathogens. It plays a key role in activating immune cells and enhancing their ability to combat infections. [restricted term] gamma is involved in regulating inflammation and promoting immune surveillance in the body. Its levels can fluctuate based on factors like fasting, impacting the immune system's effectiveness in fighting illnesses.
  • Interleukin-4 is a type of immune cell that plays a crucial role in regulating the body's immune responses. It is known for promoting the growth and differentiation of various immune cells, particularly those involved in allergic responses and fighting parasites. Additionally, interleukin-4 helps regulate inflammation and plays a role in the body's defense against infections. Its levels can be influenced by factors like fasting, as seen in the study, which can impact the overall balance of the immune system's responses.
  • Altering the balance of the body's immune defenses can impact how effectively the immune system responds to thre ...

Counterarguments

  • The study is from 2002, and more recent research may have provided updated insights into the effects of fasting on the immune system.
  • The sample size and demographics of the study participants are not mentioned, which could affect the generalizability of the findings.
  • The study only measured the short-term effects of fasting and meal replacement drinks; long-term effects on the immune system were not assessed.
  • The increase in interleukin-4 could have complex implications, as interleukin-4 has both pro-inflammatory and anti-inflammatory roles, and the overall impact on immune function is not clear from the information provided.
  • The study does not specify the composition of the meal replacement drink, which could be a significant factor in the observed increase in [restricted term] gamma levels.
  • The decrease in [restricted term] gamma levels during fasting may not necessarily translate to a weakened immune response, as the immune system is complex ...

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