Brief Answer:
Thyroid

Detailed Answer:
Thyroid antibodies in and of themselves are not a worrisome medical condition. The only known adverse effect on the body of positive thyroid antibodies is to cause the thyroid to become underactive. The person in whose blood these antibodies are found, regardless of the absolute number, is prone to developing a permanently under active thyroid. This condition is called Hypothyroidism.
There is nothing acutely dangerous about this. It is a treatable condition in which the individual essentially remains normal from the the thyroid perspective as long as (s)he takes thyroid medication regularly for life.
Note however, that just having positive antibodies alone does not commit a person to lifelong thyroid medication. The best test to determine if the thyroid antibodies have affected the thyroid or not is to go by the TSH and free T4. If the TSH remains normal as is the case here, one has to periodically monitor the TSH, every year to see if it becomes abnormal. More frequent testing is warranted if symptoms of hypothyroidism occur such as
dry skin
weight gain
hair loss
constipation
mood memory and concentration problems
heavy flow during menstrual cycles
irregular menstrual cycles
Feeling tired
Swollen feet
Swelling around the eyes

It is also possible that the person may never become hypothyroid despite having positive antibodies, although chances are small.

This is a fairly common condition worldwide and is particularly common in women.

There are special precautions for this condition when pregnancy is being planned such keeping the TSH under 2.5 before becoming pregnant, and once pregnancy is confirmed, the dose of medication needs to be increased after consulting an endocrinologist.

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Brief Answer:
Follow up

Detailed Answer:
Antibodies on higher side do not directly lead to thyroid cancer. However, the condition that results from the antibodies called Hashimoto's thyroiditis has a slightly higher risk of a specific type of thyroid cancer called lymphoma.
In general, when thyroid nodules are found in the setting of an elevated TSH, the risk of cancer is deemed higher.
These are very small risks though, and regular follow up with an endocrinologist can provide due vigilance to detect and treat these early on, with success.
Regarding treatment at this point, the TSH is not high enough to justify prompt treatment with thyroid medication. There are some factors to take into account to consider treatment. These are best discussed in person with an endocrinologist. I generally consider the presence of the following to guide decision making in favor of treatment:

1 Thyroid enlargement, particularly if visible (and felt on examination)

2 Pregnant or planning to get pregnant

3 Compelling symptoms as listed above

4 Difficulty conceiving

5 Associated problems like high cholesterol or heart disease/stroke or heart failure

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Brief Answer:
Second follow up

Detailed Answer:
Sorry I did not realize she was already on eltroxin. All the above the answers are still valid and applicable except that when I see someone like this person in my practice I optimize the dose to target a TSH of 0.4 to 2.5 with Free T4 in the high normal range .
Exercise, weight loss and immunity have no direct effect on improving this condition.
The dose of eltroxin could change over time depending on body weight changes.

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