There's a two hundred year history of people prescribing both high and low carb diets for weight loss. So how does one choose? One factor you should consider is the dangers associated with each diet.
What is a carbohydrate, anyways?
There are three types of nutrients that every body uses:
* Proteins in our diet usually come from Meat and soy products like tofu. Amino acids, the building blocks of proteins, are used to make muscles and enzymes (the proteins that do most of the work our bodies need to survive)
* Carbohydrates are sometimes described as "sugars," but they're not just white stuff in you find in the baking aisle. Simple sugars include the sugar you put in coffee; pasta, bread, and potatoes are among the source of starches, or complex carbohydrates. Most of your body uses carbs for energy, and it's the preferred energy source for the brain.
* Fats are long, chainlike molecules that are don't mix with water (oils are fats). They are an efficient way for the body to store energy.
You can see that all three nutrients are crucial for functioning. What happens if you take in more or less of a given nutrient than you need?
The Low-Fat Diet
The low-fat diet reduces fat intake, following the governmental food pyramid that suggests using fats sparingly. There are many good reasons to limit the amount of fat in your diet:
* cholesterol and fats can result in clogged up arteries, leading to heart disease and possible cardiac damage (in the form of a heart attack), stroke, and kidney disease
* fat packs a lot of calories – if you don't use those calories up in your daily activities, they will be stored in your fat cells and cause weight gain
Low-fat diets are often higher in carbohydrates than the average American's diet. Low-fat products take advantage of the fat-carbohydrate trade-off; if you compare "lowfat" cookies with their "normal" counterparts, you may notice that the fat per serving is lower but there is more carbohydrate per serving than the "normal" alternative. Because fat is flavorful, simple sugar and loads of salt may be added to lowfat products to enhance taste.
Carbohydrates are not as good a signal of satiety. In contrast, when you eat a bit of fat, your body "recognizes" it as a signal to limit the amount of intake. So, while a low-fat diet can help you stay healthy, a no-fat diet may encourage you to eat more than you need. If you make up in carb-calories what you lose in fat-grams, excess carbs will be stored as starch in the liver and fat in your fat cells! So even though your diet is low-fat, you may end up gaining weight if you eat more carbs than you use in daily activities.
Lastly, you need the right sorts of carbs to keep healthy and assist weight loss. Simple sugars are quickly absorbed and use little energy to process – in other words, they add lots of calories to your meal. In contrast, foods with more complex carbohydrates, like starches in whole grain breads – take longer for your body to absorb and use more energy. They also give your body time to recognize that you're full. Complex carbohydrates are more likely to have vitamins (like potato skins which have lots of B12) and fiber (like whole grain bread), both of which are important for good health.
Low-carb diets may help you lose weight by:
* making sure that you're satiated, since both fats are better signals to your body that "food's here!" than carbohydrates
* promoting ketosis: in ketosis / Ketones are a byproduct of burning fats and proteins instead of carbohydrates.
* leveling out your hormonal response to carbohydrates. We make the hormone insulin in response to food, particularly sugar, entering the body. It's been hypothesized that large changes in insulin levels (for example, a large increase in response to a carb-heavy meal) trigger the storage of sugars as fat.
However, if decreasing carbs increases your fat intake, serious problems can result. In some studies, about 30% of people on low-carbohydrate diets showed an increase in cholesterol levels, even if they lost weight on the diet. Studies have also shown that low-carb diets may increase in kidney problems, especially in people who already had some kidney disease.
In addition, some studies suggest that ketosis in the Atkin's diet is not caused just by fat burn but by burning muscles instead. Muscle loss does result in weight loss, but is unlikely to give you the look you want, or to help you function. Lastly ketosis can be fatal in diabetic – if you're diabetic, you should speak with your doctor before starting any diet.
Women have some special issues to think about when looking at a low-carb diet. Some studies show that people on these diets lose a lot of calcium, which makes them a bad idea for women at risk for osteopenia or osteoporosis. In addition, some low-carb diets do not include the right foods for a balanced intake of vitamins; While a few days of missed vitamins aren't a problem, chronic deficiencies can lead to skin, eye, and bone damage. And for women who are pregnant or trying to become pregnant, ketones can be dangerous for a fetus as well as for you.
Which Diet Should I Use?
The keys to weight loss are moderation and tailoring. If you're interested in losing weight, talk with your healthcare provider about tailoring a weight-loss plan that takes into account your current health and weight-loss goals. Lowering calories and balancing nutrients, rather than focusing on a single "culprit" gives you the best chance of long-term weight reduction.
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