Blood Penis and Flesh Penis: What's the Difference?
In a nutshell
Whether a penis appears small or large when flaccid says little about what it looks like when erect. A “blood penis” appears small when flaccid but grows significantly during an erection—often by more than 4 cm. A “flesh penis” is already larger when flaccid and changes very little during an erection. Both types are genetically determined, completely normal, and have no impact on sexual function or fertility.
Anyone who thinks they can infer the size of an erect penis from its flaccid size is usually wrong: When erect, “growers” and “showers” are virtually indistinguishable. What doesn’t change is the man himself—neither through surgery nor with age. What may decline over the years is the quality of the erection—but that’s a different topic.
What is a "blood penis" (grower)?
A “blood penis “—also known as a “grower”—is a colloquial term for a penis that appears relatively small when flaccid but increases significantly in size during an erection. The increase in size is often double or more than the original size.
The blood that flows into the erectile tissues during sexual arousal causes both the stiffening and the significant increase in the size of the penis.
What is a "meat penis" (Shower)?
A “fleshy penis “—also known as a “shower”—refers to the opposite: This type of penis is already relatively large when flaccid and hardly enlarges at all during an erection. The inflow of blood merely causes it to stiffen, without resulting in a significant change in size.
Blood Penis vs. Flesh Penis: The Key Differences at a Glance
Characteristic
Blood Penis (Grower)
Meat Penis (Shower)
Size when at rest
Rather small
Rather large
Increase in Size During an Erection
Thick (>4 cm, often ×2 or more)
Small (<4 cm)
Erection size
Similar to Shower
Similar to Grower
Prevalence in the general population
Not scientifically proven
Not scientifically proven
The size when flaccid does not indicate the actual size when erect.
How do I figure out my type? The 4-cm rule
A scientific distinction between the two types was proposed in a study published in 2018 in the *International Journal of Impotence Research*: If the penis grows by more than 4 cm during an erection, it is considered a “blood penis” (Grower); if it grows by less than 4 cm, it is considered a “flesh penis” (Shower). This distinction serves as a rough guide, not as an absolute medical category.
How Common Are "Blood Penis" and "Flesh Penis"? The Current State of Research
There is no scientifically sound evidence regarding how common both types actually are in the general population. The only clinical study on this topic—Yafi et al. 2018 in the International Journal of Impotence Research —examined exclusively men with erectile dysfunction and found that 26% were “growers” and 74% were “showers.” However, these figures cannot be extrapolated to healthy men: Since younger men in the study were more likely to be “Growers,” while older men are disproportionately represented in ED clinics, the distribution in this sample is systematically skewed.
European surveys, on the other hand, report rates of up to 80% for blood-filled penises—though without using representative methodology. Both figures should therefore be interpreted with caution. Reliable population data are currently lacking.
Is a blood-filled penis normal or a sign of a medical condition?
No, a blood penis is neither a medical condition nor does it require treatment. Both types—the “blood penis” and the “flesh penis”—are completely normal. The cause is genetic: The number and structure of the collagen fibers in the penile tissue determine how elastic the tissue is—and thus how much the penis grows during an erection. Both factors are determined at birth and are hereditary.
Neither the blood penis nor the flesh penis:
- has a negative effect on sexual function,
- affects fertility,
- is associated with erectile dysfunction,
- occurs as a result of prostate disorders.
Does penis type matter during sex?
A "blood penis" or a "flesh penis"—which is more attractive?
From a purely visual perspective, a fleshy penis attracts more attention when flaccid. This is because a penis that is already larger instinctively signals readiness to mate and can thus influence perceptions of male attractiveness.
Experienced partners know, however, that the size when flaccid says nothing about the actual size when erect. “Growers” and “showers” are often almost indistinguishable when erect.
What can I do if my blood penis bothers me?
If the flaccid penis is perceived as too small and causes psychological distress, professional penis enlargement is an option.
Penis enlargement does not change the type of penis—a “blood penis” does not become a “flesh penis.” The procedure enlarges the penis overall, making it larger in both the flaccid and erect states. Blood-type and flesh-type penises are two genetically determined types that cannot be converted into one another.
Can penis type change with age?
Some sources claim that a blood penis can transform into a flesh penis over the course of a person’s life. However, this claim should be viewed with a critical eye.
The only relevant study on this topic was published in 2018 in the *International Journal of Impotence Research* —based on data from just 274 men, all of whom suffered from erectile dysfunction. This is not a representative basis for making a general statement about healthy men.
What actually happens physiologically: As we age, the tissue of the penis loses elasticity, and the collagen content in the tissue changes. This can result in erections that are less firm or a penis that appears slightly smaller when flaccid. However, this is not a change in penis type, but rather a normal aging process that affects the quality of erections—not the genetically determined nature of the penis.
There is no conclusive evidence that a “blood penis” turns into a “flesh penis.” What changes is the quality of the erection—not the basic type.
Frequently Asked Questions (FAQ)
Is it possible to turn a blood penis into a meat penis?
No. Both types of penises are genetically determined and cannot be altered. Penis enlargement increases the overall size of the penis but does not change the way it changes in size during an erection.
How can I tell if I have a "blood penis" or a "flesh penis"?
As a rough rule of thumb: If the penis grows by more than 4 cm during an erection, it is a "blood penis"; if it grows by less than 4 cm, it is a "flesh penis."
What percentage of men have blood-filled penises?
This has not been scientifically established. The only clinical study (Yafi et al. 2018) examined exclusively patients with ED—a biased sample that does not allow for conclusions about the general population. European surveys cite figures of up to 80% for blood-filled penises, but there is no representative evidence to support either figure.
Does penis type affect sex?
No. What matters most are erection quality, control, and stamina—not the type of penis. When erect, “growers” and “showers” are virtually indistinguishable.
Does a "blood penis" turn into a "flesh penis" as one gets older?
Not in the strict sense. The genetically determined type does not change. What can change with age is the quality of the erection—the tissue loses elasticity and collagen. This affects the firmness and size of the erection, but it does not constitute a change in type.
The medical information provided on this website is for general information purposes only and does not replace a personal consultation with our doctors. As a tertiary medical center, we are also available for second opinions.
© Copyright Jörg Hagen, Doctor
About the author
Jörg Hagen, doctor
The author Jörg Hagen has been the medical director of UGRS International Germany since 1995 and has over 30 years of experience in penis enlargement and complex urological issues. He is regarded as one of the leading experts in the interests of patients in Europe. His international activities, excellent diagnostics and legal successes in patient rights make his assessments particularly well-founded. Patients appreciate his scientifically based, discreet and trustworthy care. His articles are based on many years of practice and well-founded information at the highest level.
This content is for general information purposes only and does not constitute medical advice, diagnosis or treatment recommendations. It is in no way a substitute for a professional examination or treatment by a licensed physician. If you have any health complaints or uncertainties, please always consult a medical professional – especially if you have questions about intimate surgery or sexual health.
