/ What's New

Can Dieting Make Our Animal Companions Fat?

Published July 24, 2012 in Dr Peto Says, Monthly Care Tips, What's New |
Tags: , | Leave a comment

A recent study in humans demonstrated that frequent episodes of intentional weight loss can actually make individuals more prone to weight gain.

Similar studies have not been conducted in animals. Because metabolic adaptations to calorie restriction appear to be universal from species to species, it is probably safe to assume that our animal companions would also be prone to weight gain with frequent bouts of weight loss.

A sustained commitment to a lifestyle change rather than the short term “yo-yo” effect of on-again, off-again dieting is probably a healthier strategy for us and our companions.

The Study

Researchers in Finland compared weight gain patterns for 2,000 sets of twins. Twins were chosen to decrease the genetic variability of metabolism and behaviour between individuals.

Subjects with a history of two or more episodes of dieting progressively gained more weight than their non-dieting co-twin over 25 years than those subjects that only dieted once compared to their non-dieting co-twin over the same time period. The researchers concluded that the diet itself promoted weight gain independent of genetics. Other research supports their claim.

Supporting Research

Studies have shown that calorie restriction or dieting promotes metabolic changes in the body to resist further weight loss. Immediate hormonal changes that occur with the feeling of hunger signals the portion of the brain that controls the thyroid gland to decrease the production of the hormone, thyroxine.

Blood levels of thyroxine determine the rate of cellular activity in the body. As thyroxine levels fall in the bloodstream, cellular activity slows and fewer calories are needed to sustain resting metabolism.

Hormonal changes also affect the active or non-resting metabolic rate of muscle and fat cells.

Dieting muscle requires less energy to perform the same task it did prior to dieting. Fat cells become resistant to breakdown for energy. In fact, the body shifts to promote fat production. Dieting cells shift to using carbohydrates for energy rather than fat, further decreasing fat loss.

Carbohydrates, fats and protein all require a portion of the calories they contain for their own digestion and absorption from the intestines. Proteins require 15-25 percent of their calories, carbs require 5-15 percent of their calories, and fats require 2-3 percent of their calories for this purpose. This is called the thermic effect of food.

During dieting, the thermic effect of food for carbs, fats, and proteins decrease so the body uses fewer calories for the digestion and absorption of food, contributing to the slowdown of weight loss.

Although there are fewer of these metabolic studies in cats and dogs, studies in both species have confirmed that weight gain after induced obesity and dieting is faster and requires fewer calories than needed to induce obesity. This would imply similar metabolic changes during dieting in cats and dogs.

What’s New with the Study

The results of the Finnish study suggest that metabolic efficiency changes have lasting effects.

Most studies follow metabolic changes over 1- 2 years, with few extending five years. The 25 year period studied by the Finnish researchers suggest that metabolic changes may last much longer and possibly indefinitely. Obviously, more research is needed to confirm this, but the implications are important. Rather than seeking diet solutions for ourselves and our companions, we should look at weight management as a complete lifestyle change in eating, feeding, and exercise habits.

Recent statistics indicate the average daily calorie intake in the U.S. across all age groups is 3,770. That is an astounding amount of calories. This is 770-1,000 more calories than needed for active men and women, and far more than necessary for children and less active individuals.

Our animal companions are also enjoying this calorie largess. This degree of overeating and overfeeding by us and our companions certainly warrants an analysis of lifestyle rather than the newest diet craze.

Selected from petMD.com


Vomiting or Regurgitation ~ An Important Distinction

Published July 16, 2012 in Dr Peto Says, Monthly Care Tips, What's New |
Tags: , | Leave a comment

Vomiting is a symptom that commonly affects both cats and dogs.

Even though vomiting is very common, one of the first things that a veterinarian has to do when faced with a “vomiting” animal companion is determine whether or not that is truly what is occurring.

Vomiting can easily be confused with regurgitation, and making the distinction between vomiting and regurgitation is crucial. Not only are their causes very different, but so are the treatments that are most likely to help.

Of course, it is ultimately the veterinarian’s job to determine whether an animal companion is vomiting or regurgitating, but it is very helpful if fur parents know what distinguishes the two conditions so they can accurately describe what they are seeing at home.

Vomiting is an active process. It involves contractions of the abdominal wall (i.e., retching) prior to the actual event and the sensation of nausea, which is often associated with excess salivation, licking of the lips, and drooling.

Regurgitation, on the other hand, is passive and may occur just after an animal companion changes position (e.g., lowers his head).

Where the material comes from is also important. Vomitus originates in the stomach and sometimes the first part of the small intestine. If you see bile, a yellow or orange digestive fluid that is produced by the liver and delivered to the small intestine, you know your companion is vomiting, but an absence of bile does not eliminate vomiting as a possibility.

Regurgitated material travels backwards from either the esophagus or pharynx into the mouth or nose. Regurgitus sometimes exits the body in the shape of a tube because of the time it spends in the esophagus and typically contains food, saliva, and some mucus but no bile.

Not to confuse matters, but another symptom that is sometimes called “vomiting” by owners is expectoration. If your animal companion coughs a few (or more) times and then gags up a glob of mucus and associated expectorus, he may well be expectorating rather than vomiting or regurgitating.

If you get the opportunity, take a video of your animal companion during one of his “episodes” before your appointment and bring it with you. That would greatly assist your veterinarian reached a definitive diagnosis faster than you expect.

Selected from petMd.com