With all of the conflicting studies and fuzzy interpretation of
information, it's no wonder that confusion reigns when it comes
to the value and safety of low-carb diets. It seems like heated
debates are raging everywhere!
Whether it's Atkins, the South Beach or some other low-carb plan,
as many as 30 million Americans are following a low-carb diet.
Advocates contend that the high amount of carbohydrates in our
diet has led to increasing problems with obesity, diabetes, and
other health problems. Critics, on the other hand, attribute
obesity and related health problems to over-consumption of
calories from any source, and lack of physical activity. Critics
also express concern that the lack of grains, fruits, and
vegetables in low-carbohydrate diets may lead to deficiencies of
some key nutrients, including fiber, vitamin C, folic acid, and
Any diet, weather low or high in carbohydrate, can produce
significant weight loss during the initial stages of the diet.
But remember, the key to successful dieting is in being able to
lose the weight permanently. Put another way, what does the scale
show a year after going off the diet?
Let's see if we can debunk some of the mystery about low-carb
diets. Below, is a listing of some relevant points taken from
recent studies and scientific literature. Please note there may
be insufficient information available to answer all questions.
- Differences Between Low-Carb Diets
There are many popular diets designed to lower carbohydrate
consumption. Reducing total carbohydrate in the diet means that
protein and fat will represent a proportionately greater amount
of the total caloric intake.
Atkins and Protein Power diets restrict carbohydrate to a point
where the body becomes ketogenic. Other low-carb diets like the
Zone and Life Without Bread are less restrictive. Some, like
Sugar Busters claim to eliminate only sugars and foods that
elevate blood sugar levels excessively.
- What We Know about Low-Carb Diets
Almost all of the studies to date have been small with a wide
variety of research objectives. Carbohydrate, caloric intake,
diet duration and participant characteristics varied greatly.
Most of the studies to date have two things in common: None of
the studies had participants with a mean age over 53 and none of
the controlled studies lasted longer than 90 days.
Information on older adults and long-term results are scarce.
Many diet studies fail to monitor the amount of exercise, and
therefore caloric expenditure, while participants are dieting.
This helps to explain discrepancies between studies.
The weight loss on low-carb diets is a function of caloric
restriction and diet duration, and not with reduced carbohydrate
intake. This finding suggests that if you want to lose weight,
you should eat fewer calories and do so over a long time period.
Little evidence exists on the long-range safety of low-carb
diets. Despite the medical community concerns, no short-term
adverse effects have been found on cholesterol, glucose, insulin
and blood-pressure levels among participants on the diets. But,
adverse effects may not show up because of the short period of
the studies. Researchers note that losing weight typically leads
to an improvement in these levels anyway, and this may offset an
increase caused by a high fat diet. The long range weight change
for low-carb and other types of diets is similar.
Most low-carb diets cause ketosis. Some of the potential
consequences are nausea, vomiting, abdominal pain, and confusion.
During the initial phase of low-carb dieting some fatigue and
constipation may be encountered. Generally, these symptoms
dissipate quickly. Ketosis may also give the breath a fruity
odor, somewhat like nail-polish remover (acetone).
Low-carb diets do not enable the consumption of more calories
than other kinds of diets, as has been often reported. A calorie
is a calorie and it doesn't matter weather they come from
carbohydrates or fat. Study discrepancies are likely the result
of uncontrolled circumstances; i.e. diet participants that cheat
on calorie consumption, calories burned during exercise, or any
number of other factors. The drop-out rate for strict (i.e. less
than 40 grams of CHO/day) low-carb diets is relatively high.
What Should You Do? - There are 3 important points I would like
- The long-range success rate for low-carb and other types of
diets is similar.
- Despite their popularity, little information exists on the
long-term efficacy and safety of low-carbohydrate diets.
- Strict low-carb diets are usually not sustainable as a normal
way of eating. Boredom usually overcomes willpower.
It is obvious after reviewing the topic, that more, well-designed
and controlled studies are needed. There just isn't a lot of good
information available, especially concerning long-range effects.
Strict low-carb diets produce ketosis which is an abnormal and
potentially stressful metabolic state. Under some circumstances
this might cause health related complications.
The diet you choose should be a blueprint for a lifetime of
better eating, not just a quick weight loss plan to reach your
weight goal. If you can't see yourself eating the prescribed
foods longer than a few days or a week, then chances are it's not
the right diet. To this end, following a moderately low fat diet
with a healthy balance of fat, protein, carbohydrate and other
nutrients is beneficial.
If you do decide to follow a low-carb plan, remember that certain
dietary fats are associated with reduction of disease. Foods high
in unsaturated fats that are free of trans-fatty acids such as
olive oil, fish, flax seeds, and nuts are preferred to fats from
Even promoters of the Atkins diet now say people on their plan
should limit the amount of red meat and saturated fat they eat.
Atkins representatives are telling health professionals that only
20 percent of a dieter's calories should come from saturated fat
(i.e. meat, cheese, butter). This change comes as Atkins faces
competition from other popular low-carb diets that call for less
saturated fat, such as the South Beach diet plan. Low-carb
dieting should not be considered as a license to gorge on red
Another alternative to "strict" low-carb dieting would be to give
up some of the bad carbohydrate foods but not "throw out the baby
with the bath water". In other words, foods high in processed
sugar, snacks, and white bread would be avoided, but foods high
in complex carbohydrates such as fruit, potatoes and whole