Question #10: Does eating sugar make you more likely to get sick?

A question from email and a complicated one.. the answer is yes... and well no.

One thing we must consider is the health of the person consuming the sugar in question. Those with immune diseases, diabetes, leukemia and digestive disorders (among other conditions) are going to have different experiences on health in this case than the average, healthy individual. Age and body size can also affect the case related to this question, partially, due to the body mass to sugar intake ratio. Of course a 40lbs child will be more effected by the large quantities of sugar than a 150lbs adult.

So, for the sake of this discussion we are going to assume that the individuals consuming the sugar is a healthy, average sized adult with no health conditions that will increase or decrease the effects of the sugar on the body.

The background

The only study discussing sugar and the immune system revolves around the behavior of neutrophils. Neutrophils are one type of immune cell found in the body. They are often in the blood but can also be found at sites of infection or cancer. These cells are usually the first ones to respond to infection or cancer due to their phagocytic nature, i.e. they come in and devour  the foreign or cancerous cells. There are several types of neutrophils that respond to different stimuli. The study does not seem to list which type(s) of neutrophils they are observing. This is problematic for deducing the actual impact of the sugar on the specific parts of the immune system.

The 1973 study I read started with individuals who have fasted. This means that they have not consumed food in 12-24 hours. Their body would be processing stored sugars at this point after exhausting the blood sugar (sugar in the blood). The subjects are then dosed with 20 or more teaspoons of sugar (different sources are used in studies such as honey, fructose, glucose, etc.) are then administered. After a wait time blood is drawn and added to a culture of bacteria. The neutrophil or other white blood cell activity is observed.

What did I find?

Aside from the 1973 study, which by science standards would be considered way out of date, I didn't uncover any scientific papers in peer reviewed journals that discussed humans and sugar intake. I was very disappointed as I searched around many distributors such as PubMed, EBSCOHost and several others and found nothing. I even tried different sugars to see if there would be papers for glucose or fructose instead of just sugar. I had no luck. I did find lots and lots of blogs and unreferenced sources that harken back to the 1973 study or no study at all.

What does that mean? Well there is one, outdated source, that suggest there may be a link. I say outdated because in most fields, particularly medicine, articles over 10 years old are considered sketchy to use and those 20 years or more are considered obsolete. The study suggests that it is the large inflow of sugar into the blood stream after fasting that depresses the immune system. The neutrophils are still working just a little slower.

Does this mean I will get sick from drinking a can of soda? No, probably not. Everything in moderation is how I have always felt. Perhaps with the recent interest in the subject more studies will be done to clarify what the outcome truly is. Below are links to the study and some relevant sources. Sadly, I can't give a better answer to this question until there is more research to read.


Sources:
Information about White Blood Cells
Blog Post about Immune System Cells
1973 Study most often cited
Blog post summarizing the study.
USA Today discussion of the study
Mouse Study - Note that the mice here are give 50g/kg of sugars which is much, much higher sugar to body weight dose than was used in the human study.
Another article that examines the study and raises the fact that no studies have really been conducted since 1973.
Another mouse study but it isn't only high sugar given but also high fat and cholesterol.

Question #6 Why doesn't ice cream melt when you fry it?

This is a question I get asked a lot so I figured I would answer it now.

The first thing we need to discuss is freezing temperatures. For water it is 32 F (0 C) but milk is a little different. Due to the fact milk has solids dissolved in it, fats, proteins, etc. the freezing point of milk is 31.028 F or -0.5400 C. A little aside, one of the ways they determine if milk is watered down by a supplier or if the cow producing it is sick is they check the freezing point of the milk. If the freezing point is 32 F (0 C) then there is something wrong with the milk. Back to the ice cream. Ice cream freezes solid at about 5 F (-15 C). Most home freezers keep ice cream at or near this temperature. 

When we think about a scoop of ice cream melting that means that the temperature of that ice cream has raised from whatever temperature it was in the freezer to something between 5 F and 31 F. The higher the temperature the more milk like it is. The trick with fried ice cream is figuring out a way to dunk a scoop of ice cream into 160-190 F (71- 88 C) boiling oil in a fryer. How can we do this without the temperature of the ice cream reaching a point where it will melt?

There are a few things going on with fried ice cream.

First, most establishments that make fried ice cream chill the scoops of ice cream to a temperature that is colder than the ice cream they serve without frying. This gives a few extra degrees before melting starts. Sometimes extra large scoops of ice cream are also used to help have more of a core to keep the ice cream solid.

Second, the pie crust like shell on the ice cream insulates the ice cream from coming into direct contact with the hot oil. (Other possible crusts are tempura batter, corn flakes, nuts, cookie crumbs, tortillas,

Finally, the time that the ball is in the hot oil is just a few seconds. No more is needed because the shell is thin and cooks quickly.


Basically. you have extra cold ice cream in insulation (the crust) dipped in hot oil for an incredibly short period of time. This allows the ice cream to stay solid. If you let your fried ice cream sit too long the heat from the shell will reach the inside and begin to melt the ice cream. This is why fried ice cream is a dessert to eat immediately.