Comments on: Antibiotics fuel obesity by creating microbe upheavals

By: Lori

Lori — Mon, 10 Sep 2012 19:45:10 +0000

@Shawn
Actual children get low doses of antibiotics constantly throughout the day if they eat any non organic animal products. Not to mention if there is any in their tap water! That is why when kids get sick they really get sick now. Several of my friends have their kids at the Dr. getting antibiotics at least once a month and several are now immune to all that are available in the US. They have to wait weeks while stuff in flown in from over seas!

By: zach k

zach k — Mon, 27 Aug 2012 19:07:40 +0000

@1 – I am a grad student in the Blaser lab – fecal transplants to young, germ free mice from antibiotic treated mice have a similar effects on fat gain as sub-theraputic antibiotic treatment even if no antibiotics are given. (upcoming data!)

By: Shawn

Shawn — Mon, 27 Aug 2012 01:52:28 +0000

An now, for extra points:

Science has shown that feeding low levels of antibiotics to animals makes them put on weight faster. Feeding low-level antibiotics to humans will:

a) make them put on weight.
b) make them lose weight.
c) not change their weight gain.
d) none of the above.

By: vince

vince — Sat, 25 Aug 2012 09:40:22 +0000

possible follow up tests

1. more animals aside from rats/mice
2. instead of prolonged doses of antibiotics, try say 1 week doses 2-3x a year, mimicking actual human use
3. after long term antibiotic treatment, try various probiotics and see if body fat goes down
4. in totally germ free rats (raised generation after generation in aseptic conditions), inoculate them with known bad or good bacteria and see what happens

By: Stephen Cherniske

Stephen Cherniske — Sat, 25 Aug 2012 01:34:15 +0000

Certainly, antibiotics should be used sparingly. How many parents believe that as soon as a child’s snot turns green, an antibiotic is required. That is simply not true, but I have heard it from pediatricians! This article, and others describing the emergence of supergerms, brings us to a difficult realization; that we have interfered with natural selection in a profound way. Could it be that in trying to protect and preserve the weakest (certainly a noble goal) we have endangered even the strongest? Time will tell.

By: Ed Yong

Ed Yong — Sat, 25 Aug 2012 00:43:55 +0000

Yes, but a LOT of things have changed since then, including big trends in diet and physical activity.

Let’s not go overboard here.

This isn’t THE explanation for the obesity epidemic, because such an explanation does not exist. Obesity is a multi-factorial problem with lots and lots of different interacting causes. What this tells us is that antibiotic exposure and microbiome disruption may be part of that.

By: Johan

Johan — Fri, 24 Aug 2012 15:37:37 +0000

This is really interesting. If you look at obesity rates by age group there is a big increase for people born after the introduction of penicillin.

By: Sharon

Sharon — Fri, 24 Aug 2012 14:12:54 +0000

This is not an easy correlation. I agree more needs to be done to understand what is a healthy balance.

I have a lot of kittens go through my hands, and upper respiratory infections are common. That means antibiotics – sometimes weeks of different medicines because these fellows can be rescued from anywhere with all sorts of crud. Some need way more than a week of amoxi.

Over time, some of my foster kittens stay with me so long they grow up into cats so there is a list of factors that could make them fat – antibiotics, neutering, grain in their dry food …

However, my cats are all active and mostly eat a meat diet, rather than dry. Diet and life style is different than mice, and different than people.

I currently have no fat cats in the house, and I can’t remember having a plump cat for years. Not all the cats in my house are young adult age either. This is anecdotal, but also illustrates that mice and antibiotics studies only gives a hint, rather than the answer.

By: Mary

Mary — Fri, 24 Aug 2012 13:01:27 +0000

It could be the thing that finally gets some parents to understand that every viral infection should not get antibiotics. And that would be good. But if it delays treatments for real bacterial situations that need intervention, kids could suffer.

But let’s not go too far with an idea that non-first-world guts would be ideal. There are also studies that show infections in these kids can be setting back brain development.

By: Bruce Clement

Bruce Clement — Fri, 24 Aug 2012 08:11:14 +0000

@Fenella

It’s possible that people on first world diets may never obtain “normal” ratios of gut bacteria. Back in May Ed did an article http://blogs.discovermagazine.com/notrocketscience/2012/05/09/three-nations-divided-by-common-gut-bacteria/ on differences between the intestinal biomes of people in the US, Venezuela and Malawi.

“The Malawian and Venezuelan babies also had more genes for harvesting the readily available sugars in breast milk, although these dwindle away as they get older. As their diet shifts towards high-fibre foods like corn and cassava, their gut bacteria become loaded with genes for breaking down more complex sugars and starches. For American babies, the opposite is true. With a lifelong diet of refined sugars ahead of them, the genes for harvesting these nutrients become more abundant as they get older. And since they eat high-protein diets, their gut bacteria become rife with genes for breaking down amino acids.”

It will be interesting to watch this play out. How much of the change is from antibiotics and how much is from diet and lifestyle is a story that doesn’t seem to be completely told yet.