Protein and Its Role in PCOS

An increased intake may reduce weight and diabetes risk

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Protein is one of three nutrients that provide calories alongside carbohydrates and fat. Protein functions as the building blocks for bones, muscles, skin, and blood as well as the enzymes, hormones, and vitamins your body needs to function normally. If you have polycystic ovary disease (PCOS), eating a diet higher in protein and lower in carbohydrates may help overcome weight gain and diabetes common in women living with the disease.

Function of Protein

Proteins are made up of a chain of amino acids and differ in size and structure depending on how the body puts them together. The sequence by which proteins are constructed is directed by the information encoded in genes. Once built, the protein "building blocks" can bind to other molecules and each other to carry out a variety of essential functions in the human body.

Among them:

  • Proteins are responsible for the growth and maintenance of all cells and structures. including bone, muscle, cartilages, blood cells, skin, and hair.
  • Proteins are also the primary component of enzymes that facilitate chemical reactions in the body, including digestion and metabolism (the conversion of calories into energy).
  • Proteins are also integral in the production of hormones such as insulin, thyroid hormones, estrogen, and testosterone.
  • Proteins aid in immunity by building the antibodies that the immune system uses for defense and the antigens that differentiate harmful cells from normal ones.

Once formed, proteins have a limited life span and are broken down—over a period of minutes to years—in a process called protein turnover. In order to ensure normal biological function, you need to obtain protein from the foods you eat in ample quantities.

Types of Dietary Protein

The human body can synthesize 11 of the 20 amino acids that it needs to build protein. The remaining nine must be obtained from the foods you eat. These are referred to as essential amino acids.

When a single food contains all nine essential amino acids, it is called a complete protein. At other times, different sources of protein must be eaten—some of which contain a high concentration of certain amino acids but little or none of the others—to obtain all of the nine amino acids you need. Foods that fail to deliver all nine are referred to as incomplete proteins. When foods are combined to create a complete protein profile, they are called complementary proteins.

Whenever you eat protein, the stomach, pancreas, and liver secrete digestive acids and enzymes that break them down into their basic amino acid structure so that they can be absorbed by the intestines and transferred to the bloodstream.

From there, they go to the liver where amino acid use is regulated. Some of the amino acids will be synthesized into important proteins in the liver; others will be sent elsewhere in the body for different uses.

Food Sources

Dietary protein is derived from two different sources: plant-based sources (such as soy, nuts, and beans), or animal-based sources (such as meat, poultry, fish, dairy, and eggs).

With the exception of soy, animal-based proteins are the only complete proteins, delivering all of the essential amino acids you need in sufficient amounts.

Plant-based proteins offer various types and amounts of essential amino acids and, as such, are considered incomplete proteins. Because of this, vegans and vegetarians typically rely on a variety of plant-based proteins to ensure they get all nine essential amino acids.

For example, grains are low in the amino acid lysine, while beans and nuts are low in methionine. When grains and legumes are combined (such as rice and beans or peanut butter on whole wheat bread), they form a complete complementary protein.

Dietary Requirements

Protein requirements differ according to age, sex, weight, and activity level. According to the 2015-2020 Dietary Guidelines for Americans issued by the Office of Health Promotion and Disease Prevention, the daily recommended intake of protein is as follows:

Recommended Dietary Intake of Protein in Grams (g)
Age Female Male
1-3 13 g 13 g
4-8 19 g 19 g
9-13 34 g 34 g
14-18 46 g 52 g
19-30 46 g 56 g
31-50 46 g 56 g
51 and oer 46 g 56 g

These recommendations serve as general guidelines given that people with higher activity levels (such as athletes) will invariably require a higher intake of protein than someone who is sedentary.

Some conditions, like advanced kidney disease, may require a lower intake of protein, while others, like PCOS, may benefit from a higher intake.

Protein and PCOS

Weight gain and obesity are common in women with PCOS. In the past, much of the focus was placed on the restriction of foods to help women with PCOS achieve and sustain weight loss. Today, there is strong evidence that the balance of foods you eat, namely protein and carbohydrate, play as significant a role in weight loss as routine exercise and the reduction of calories.

According to a 2012 study published in the American Journal of Clinical Nutrition, replacing carbohydrates with high-quality proteins do more to achieve weight loss than a standard, well-balanced diet.

The study involved 57 women with PCOS who were given either a standard diet (with less than 15% of energy from protein and 30% from fat) or a high-protein diet (with more than 40% of energy from protein and 30% from fat). After six months, women given the high-protein diet had greater weight loss (16.9 pounds vs. 7.3 pounds) and greater loss of body fat (14.1 pounds vs. 4.6 pounds) as well as significantly reduced waist circumference.

A high-protein diet can also help achieve sustained decreases in blood sugar (glucose). This can help reduce the risk of type 2 diabetes, a condition that affects roughly 40% of all women with PCOS by the age of 40.

A Word From Verywell

If you have PCOS and struggle with weight or blood sugar control, ask your doctor for a referral to a board-certified dietitian experienced in metabolic disorders. By working with a doctor and dietitian, you can find a dietary strategy that is not only sustainable but safe.

Avoid fad diets that promise quick fixes. These typically restrict important food groups and nutrients that your body needs to function normally. Instead, find a sensible diet plan that you can maintain for a lifetime, one that provides you with the right balance of protein, carbohydrates, and fat for your age, weight, and medical condition.

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Article Sources

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