The thyroid gland, located near the "Adam's apple" in your neck, has the vital function of controlling your body's metabolism. Diseases that impair the function of this gland can lead to depression, fatigue, weight gain, joint pain, hair loss, slowing of your metabolism and increased risk for heart disease. Diets higher in lean and balanced protein sources support thyroid function.
Effects of Low-Protein Diets
According to nutritional counsellor Dr. Ray Peat, diets low in protein or composed of an imbalance of protein sources stress the body, causing suppression of the thyroid gland. This type of diet can also reduce the body's response to thyroid hormone supplements and further lower overall metabolism. Dr. Peat reports that diets relying too heavily on either vegetable or meat sources alone for overall protein intake lack sufficient balance.
The Right Amount of Protein
In her book "The Thyroid Diet", Mary J. Shomon recommends that each of our three daily meals include one to two portions of lean protein. You can kick start your metabolism in the morning by including at least 20 g of protein with breakfast. Daily protein intake should be as much as 70-100 g.
Vegetable sources alone may not provide sufficient quantities or quality of protein while diets high in meat proteins may overwhelm the body with amino acids. Dr. Peat recommends balancing protein sources, including a quart of milk per day combined with cheeses, nuts, shellfish and potatoes. Other lean protein options include fish, skinless turkey or chicken breast, and limited amounts of lean cuts of meat such as beef, lamb or pork.
Soy Protein and Thyroid
Soy protein has been found to suppress thyroid function due to its' plant based estrogen content. According to Dr. Peat, estrogen inhibits the release of thyroid hormones and can lead to hypothyroidism or under-active thyroid. Large amounts of dietary soy should be avoided, particularly if you have a condition that already suppresses your thyroid function.
Heart Health Considerations
An under-active thyroid gland can increase cholesterol levels, including low density lipoproteins or bad cholesterols in your blood. Untreated, this can double your risk for heart attack. If you are increasing your daily protein intake it is important to avoid high fat sources and stick to lean proteins to avoid increasing your risk.