Starting a Low-Carb Diet for Weight Loss

Reducing carbohydrate intake is a popular way to try to meet a weight loss goal. When you start eating fewer carbs, the way your body recruits energy will change, which will make you feel different physically and even emotionally.

What Is a Low-Carb Diet for Weight Loss?

The definition of a low-carbohydrate diet is loose. For some people, it may mean casually reducing their refined carb intake, but for others, it might mean reducing total carbohydrate content to a specific goal. Most low-carb diets aim for 50 grams of carbohydrate per day, though some lower-carb eating plans allow for up to 150 grams of carbohydrates per day.

While research has shown that people can lose weight on low-carb diets, there is no guarantee that you'll have the same experience. However, most people can expect to lose some weight when they make dietary changes like reducing their carbohydrate intake.

Physical Changes When You Start a Low-Carb Diet

Knowing what your body does in response to dietary changes can inform your weight loss estimates and keep you on the right track as you progress.

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Common Mistakes to Avoid When Starting a Low-Carb Diet

Metabolism Shifts

During the first week following a low-carb eating plan, there will be a shift in your body's metabolism. Instead of primarily using carbohydrates for energy, your body will switch to other sources.

If you consume fewer than 50 grams of carbohydrates per day, your body is likely to activate a process called gluconeogenesis, where energy is created by breaking down non-carbohdyrate sources (such as certain lactic acids or amino acids). If your body still cannot make enough glucose by gluconeogenesis, your body will begin to make ketone bodies (from stored fat) as an alternative for fuel.

In terms of specific weight loss, some research suggests that people lose approximately the same amount of weight on a low-carb diet as on a low-calorie diet.

Some weight loss at the outset is normal, but at this stage, you're losing water weight, not body fat. The glucose stored in the liver that is readily available for energy takes the form of a molecule called glycogen, and these molecules are bound up with a lot of water. When you first start a low-carb diet, the stored glycogen is released and broken down, along with the water that comes with it.

Initial Weight Loss

People who restrict carbohydrate intake to less than 50 grams a day (which is considered a very low-carb diet) typically see a more profound loss at the very beginning than those who stick to a diet that includes 60 to 130 grams of carbohydrates daily.

However, since the average American diet contains about 200 to 300 grams of carbohydrates daily, any reduction in carbs is likely to produce a change.

After a week of roller-coaster-like metabolic shifts, the second week of a low-carb diet is much more stable. If you respond well to a low-carb diet, this is the point at which most people will begin to experience fat loss. If you're not seeing changes, don't despair: Some bodies take a little longer to adjust. Patience is key!

If you choose to track your weight loss with a scale, how you weigh yourself is important. Here are some tips:

  • Be consistent. Choose a consistent time of day to weigh yourself. This makes the best possible basis for comparison.
  • Consider your cycle. If you are having a menstrual cycle, you may decide not to weigh yourself during the second half of your cycle—especially if you tend to retain water.
  • Limit your weigh-ins. The usual advice is to weigh yourself once a week instead of every day. The normal day-to-day weight fluctuations come from your body's fluid balance, how much fiber you eat, and other factors.

During the second half of the first month on a low-carb diet, your body will usually begin to settle into a pattern of weight loss. Your weight loss rate will depend on many factors, including how much weight you have to lose. People who begin a low-carb diet with less fat to lose generally lose weight more slowly than those who started out with more.

After the first couple of weeks on a low-carb diet, people may lose between 1/2 pound and 2 pounds a week, which is considered a more sustainable rate of weight loss.

Weight Loss Plateaus

If you're anxiously tracking lost pounds, shifts in water weight may be troubling for you. Even when you're losing body fat, fluctuations in fluid levels can make it look like you're experiencing a stall in weight loss (sometimes referred to as a plateau).

As your body is adjusting, try to avoid becoming too focused on the scale. Remember that weight loss takes time and consistency.

Emotional Changes

Changing the way you eat not only has physical effects but can also affect mental and emotional health. Low-carb diets are no exception.

Mood

There are important physiological changes going on that can affect your mood as you start a low-carb diet. It's not uncommon to crave carbs, especially at the beginning of a low-carb diet. Remember that shift in your body's metabolism? As your body transitions to getting energy from glycogen to fat stores, you might feel sluggish, fatigued, and even increased irritability.

Studies have examined whether low-carb diets have an impact on prevalence of depression and anxiety. So far, no studies have been able to find a distinct link between these common mental health disorders and low-carb eating. However, some studies have shown an improvement in psychological outcomes among people doing diet programs. More long-term research is needed to understand this correlation.

Some people may find relief from these symptoms by drinking a cup of broth or eating low-sugar fruit, such as berries, melons, or stone fruit (like nectarines).

Appetite and Satiety

Carbohydrate reduction seems to work on the appetite in multiple ways, such as by altering levels of hormones that regulate your body's hunger and satiety signals. A low-carb diet may reduce your body's desire to eat more, which inherently reduces your calorie intake.

Aim to choose healthy sources of protein and fats (namely monounsaturated and polyunsaturated fats) most of the time, including:

  • Avocado
  • Healthy fat-rich fish, like salmon
  • Nuts and seeds
  • Olive oil

Fruits and vegetables will be a staple of your diet, but be sure to focus on low-carb options such as:

A Word From Verywell

If you find a low-carb diet helps you manage your weight and you don't feel deprived of high-carb foods, it may be the right option for you. It's worth noting that some studies have shown low-carb diets may be challenging to stay on for a long period of time. It is also important to make sure you are getting the proper amount of micronutrients on a low-carb diet.

When you're thinking about changing your eating habits, keep in mind that you're most likely to stick with an eating plan that includes healthy foods you enjoy and produces results. Before beginning any diet, check with a healthcare provider to make sure the plan you're considering is a safe option for you.

Frequently Asked Questions

  • How long does it take to see weight loss on a low-carb diet?

    The truth about low-carb diets for weight loss is that it's very difficult to predict who will lose weight, how much they will lose, and how long it will take. Most people will see a lower number on the scale initially, which accounts for lost water weight. Body fat loss takes longer, and losing half a pound to 2 pounds lost per week is considered an ideal pace.

  • What do I need to be careful of on a low-carb diet for weight loss?

    Avoid some common mistakes of eating a low-carb diet, such as not eating enough carbs and fiber, not getting enough fat and protein, and not eating enough fruits and veggies. Be careful of foods modified to be low in carbohydrates, as they often are highly processed and may contain additives with a high glycemic index.

  • Should you exercise when starting a low-carb diet?

    Being active rather than sedentary is always smart. Furthermore, a study published in Clinical Nutrition showed that a low-carb diet paired with exercise helped regulate blood pressure, cholesterol, triglycerides, and obesity, all metabolic factors of cardiovascular disease.

  • How do I ask for support when starting a low-carb diet for weight loss?

    Any change in eating habits can be difficult, and finding support will help you on your way to success. Ask a healthcare provider for advice. Seek out others who are following similar eating plans on online forums. You may also consider telling people close to you about your low-carb diet if you are comfortable sharing and think they will be supportive.

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6 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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