Tag Archives: cancer

On immortality: a very human desire

If presented with the fountain of youth, would you drink?

People have entertained the idea of immortality across time. Greek mythology tells of the phoenix, a bird capable of rebirth. The prominence of comics as a publication medium early in the twentieth century gave rise to a slew of superheroes capable of super-regeneration and longevity, like Superman and Wolverine. Even Lord Voldemort [SPOILER: highlight to reveal] went through the trouble of creating seven horcruxes to secure a strong hold of the living realm. Why are we fascinated with the concept of immortality?

The motivation to discuss immortality is probably related to people’s natural aversion to death and aging. There are plenty of cosmetic products and procedures that generate a lot of revenue by reversing the effects of aging, such as Botox. But what if instead of merely combating the symptoms of aging, you could eliminate it completely?

Certain examples of non-aging exist in nature. Hydras have been observed to not age. While not quite immortal, lobsters have shown to not be strongly affected by age. What can we learn from these organisms?


In DNA replication, DNA polymerase takes up a short space on the sequence that it doesn’t copy, like painting itself into the corner of a room. Image from ClipartHeaven.

At the ends of our DNA strands are sections called telomeres – repeats of nucleotides that prevent degradation of the gene as it replicates over time. Every time a cell divides, the telomeres get shorter. After many replications at a point called the Hayflick limit, the telomeres reach a critically short length and the cell stops dividing. In a way, telomere length is like a biological clock that can be used to determine lifespan.

Cells also produce an enzyme called telomerase, which adds nucleotide bases to the ends of telomeres. However, the rate of telomerases’ repair of the telomeres is overcome by the rate of cell division, so telomeres continue to grow shorter and the cell ages.


6_telomere_2 6_telomere_3 6_telomere_4
Telomerase. Here, “senescence” means “old age”. Images from the National Institutes of Health.

So does the answer to immortality lie in telomerases? Not quite. High telomerase activity is detectable in more than 90% of malignant tumours. The action of telomerase can provide cells with the capacity to infinitely replicate – a defining factor of tumour cells.

So where does this bring us? We aren’t any closer to living forever, but average life expectancy has risen over time, owing to advancing medicine and lower infant mortality rates. Still, it is just as interesting to ponder how one might spend lottery winnings as it is amusing to think about what one would do with unlimited time. Perhaps the search shouldn’t be for biological immortality, but to leave an immortal legacy. As A. A. Milne had said, “I suppose that every one of us hopes secretly for immortality; to leave… a name behind him which will live forever in this world.”


“Life Expectancy at Birth by Region 1950-2050” by Rcragun from Wikipedia.

– Trevor Tsang

The Benefits of Fad Diets: The Ketogenic Diet

Dieting is one of the hottest topics of the 21st Century, as many different diet plans surface the internet each day. According to the summary by Medical News Today, the most talked about diets include the Atkins Diet,  Zone Diet, Vegetarian Diet, Vegan Diet, Weight Watchers Diet, South Beach Diet, Raw Food Diet, and Mediterranean Diet. Different types of diets are chosen depending on the lifestyle people aim for. However, there is one type of diet that has been raved about in the medical field. The Ketogenic Diet, first developed in the 1920’s to treat epilepsy, has now become a recommended diet for tumor patients.

The Ketogenic Diet and a normal diet differ in the amount of macronutrients eaten. In a normal diet, people eat large amounts of carbohydrates, which is then broken down into glucose by insulin. These glucose molecules are used by cells as an energy source. However, when glucose sources become depleted, normal cells can gain energy through other sources like stored fats. Tumor cells cannot find any other way to gain energy and heavily rely on glucose as the only energy source. Therefore, by restricting the intake level of carbohydrates, the glucose levels become depleted and tumor cells die from a lack of energy source.


Structures of glucose and carbohydrates. Credit: Blend Space

The Ketogenic Diet works by restricting the intake of carbohydrates to the lowest amount while increasing the intake of fats and proteins to maintain sufficient energy levels.


Credit: Meta Ketosis

The diet typically consists of high fat consumption (70-75% of total calories), moderate protein consumption (20-25% of total calories), and low carbohydrate consumption (5-10% of total calories).


More bacon please! Credit: Vanity Buzz

The high fat consumption compensates for the low carbohydrate intake. Thus, normal cells begin to breakdown fats for energy. The moderate protein consumption controls the amount of insulin, which further prevents the breakdown of glucose. In addition, high insulin levels restrict ketosis from occurring.

As humans’ main source of fuel, diets play an important role in every individual’s health. As healthy individuals we should follow a regular diet instead of pursuing fad diets. However, special diet plans such as the Atkins Diet is still useful in the medical field for improving the health of tumor patients, and should not be easily overlooked. If you’re interested, please take a look at this video to see how this man beat cancer with the Ketogenic Diet:

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Stephanie Lam