Where Have All the Little Wigglers Gone, Long Time Passing?

Stumbling down the path of apathy and population decline, one meal at a time…

Small crystals of the polyamine spermine were first observed in 1678 by Antonie van Leeuwenhoek, the Dutch microscopist, in a congealed sample of his own semen. Wang et al., 2004, have since shown that spermine is necessary for male mouse fertility inasmuch as a lack of this polyamine prevents the development of spermatozoa within their testes.¹ This relatively recent observation makes sense of Fair et al.’s earlier (1972) observation that human sperm concentration (sperm count/ml) is positively and directly related to the spermine concentration of the semen:

Keep in mind while you read through this post that the Fair et al. (1972) paper containing the above graph came out of Stanford – the same university that was at the same time hosting Paul and Anne Erlich, authors of the 1968 book, “The Population Bomb”.

Given that the dietarily-elevated levels of polyamines like spermine and spermidine (each transformable to the other) are associated with less all-cause human mortality, it is not surprising that it has been repeatedly found that those suffering from male infertility consistently also exhibit more than normal all-cause mortality rates (Eisenberg et al., 2014; Eisenberg et al., 2016; and Jensen et al., 2009).

Since at least 1973, there has been an ongoing decline of average male fertility in North America, Europe, Australia, and New Zealand. The most exhaustive study of the matter found the results shown in the two graphs below. Average sperm concentration in ejaculate of adults in these Western countries declined about 52% between 1973 and 2011, while total sperm count per ejaculation dipped a little over 59% during the same period in college and armed forces age Western males. In examining the graphs below, keep in mind that a minimum sperm concentration of 15 million sperm per milliliter, or a minimum total sperm count of 39 million sperm per ejaculation, is necessary for the accomplishment of medically-unassisted female fertilization.

Source. “Unselected Western” are young college and military-age males with no known offspring, while “Fertile Western” are males with children or a pregnant spouse. “Unselected Other” are young males from non-Western nations in Asia, South America, and Africa without known offspring and “Fertile Other” are males from the same countries with children or a pregnant spouse. Note that the overall trend for average Western males (i.e., Unselected Western) over the 1973-2011 time period is steeply negative for both sperm concentration and total sperm count/ejaculation. The negative slope is less steep for Fertile Western males. Non-Westerner average males have seen a more gradual decline in overall fertility than Westerners, but fertile non-westerners – the ‘marrying kind’ (Fertile Other) have gradually enjoyed an increase in potency over the last several decades.

As you can see in the above graphs, the sperm concentration and total sperm count values for the average young male Westerner in 2011 were both marginal for the purposes of helping to create offspring, verging on medical oligospermia. Both 2011 male fertility measurements are very near or at those necessitating artificial insemination of a woman in order to successfully achieve fertilization and pregnancy.

So, the coupling of increased all-cause mortality with infertility in Western males suggests the possibility that a sustained and increasing dietary polyamine deficit is behind both developments in Western males. Is there any evidence to support this hypothesis?

First, returning to the Zoumas-Morse et al. (2007) data showing the richest polyamine food sources in the typical American diet (Table 1), it can be seen that:

1. Fresh corn, grapefruit juice, oranges, and orange juice, are the four richest sources of putrescine in the average American diet;

2. Fresh corn, green pea soup, pears, and cheese enchiladas are the top four richest food sources of spermidine in the US diet; and,

3. Green pea soup, chicken liver, chili with meat and beans, chicken breast, and various legume-based foods (peas and beans) are the top five richest food sources of spermine in the typical American diet.

Keep in mind that putrescine can be converted to spermidine, and spermidine can be converted to spermine (Wikipedia). This means that dietary polyamines gained from eating any of the foods listed above can be used to supply needed spermidine to reduce all-cause male mortality – and/or to supply the spermine evidently required to insure and maintain human male fertility.

“The polyamines undergo rapid interconversion in the polyamine cycle, in which putrescine leads to synthesis of spermidine and spermine, with degradation of these polyamines to form putrescine, which can begin the cycle again” (Wikipedia).

Aggregate USDA per capita US consumption data for fresh sweet corn, canned sweet corn, and frozen sweet corn is illustrated in the next graph. Sweet corn is, by far, the richest and most dietarily-abundant source of both putrescine and spermidine in the general American diet. American per capita consumption of this most important spermidine and putrescine food source, however, has precipitously fallen over the exact same period of time as has American male fertility.

Turning to time series records of per capita citrus fruit consumption, it is clear that American consumption of our second richest source of putrescine has also declined steadily over the same period of time as the nation’s overall male fertility.

And further USDA economic data show that US consumption of peas, the richest common American food source of spermine, has also markedly and continuously decreased over the period of time that American male fertility has decreased. This decline, however, rapidly and strongly reversed itself at about the 2011 nadir of the fertility in young Western males.

To potentially make these matters worse, the results of a small prospective study suggest that low cellular levels of spermine and spermidine can lead to, among several other things, low testosterone levels and therefore low libido in both sexes. Supplementation² with these two polyamines, on the other hand, appears likely to be corrective in more ways than one.

I have no firm idea why Americans began simultaneously eating less and less of the three major types of polyamine-rich food in the US diet that especially support male (and female) fertility in or about 1970. Maybe it’s something Stanford Univeristy’s Paul and Anne Erhlich (or some of their many readers) somehow triggered with their 1968 book, The Population Bomb. I suppose a federal government nudge-nudging of the US food industries over that long time period would have been feasible by judicious and continuing juggling of the USDA farm support program.

In any case, I am glad to see the eating of peas and other lentils is back in fashion in America. Now only for a similar return to citrus fruits and sweet corn.

May all of our male and female testosterone and libido levels begin rising again, along with our former native male and female fertility…

1. Not discussed here, but polyamines are similarly critical to maintaining female fertility. See https://pubmed.ncbi.nlm.nih.gov/34099041/ for example.

2. The authors of this paper did not disclose the daily amount of sublingual spermidine and spermine provided to their study subjects. However, later-published marketing materials directly associated with this commercial research effort indicate 2.5 mg/day supplementation of both polyamines. This is in line with the small amounts of spermidine found to be effective in reducing all-cause mortality by Kiechl et al., 2018. To confirm this dose tracking, see https://nokomisresearch.com/products/ and then https://belllifestyleproducts.ca/products/new-6-eroxil-for-men (It’s far, far cheaper to just eat corn or peas, and imbibe in citrus fruits.)