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Frequently Asked Questions


Cholesterol

Why do doctors talk about good and bad cholesterol? I thought cholesterol is always bad.


Diabetes

My doctor said my diabetes need insulin after years of using pills. Why?


Why is it important to take good care of the feet in diabetes?


What are Type 1- and Type 2-Diabetes?


What is the relationship between obesity and diabetes?


Why is diabetes treated with pills in some patients while others need insulin?


Growth Hormone

I read on the Internet that growth hormone could be good for the elderly. Is this an accepted treatment?


Hormones - Acne

Is acne a sign of hormonal imbalance?


Hormones - Birth Control

Do birth control pills increase weight?


Hormones - Prolactin

What is prolactin? Doctors say an excess of it caused me to lose my periods.


Hormones- Impotence

Is impotence an indication of a "hormonal" problem?


Menopause

What is menopause?


Is it safe to take hormones after menopause?


Osteoporosis

What is osteoporosis?


What is bone density or bone densitometry?


What are Actonel, Fosamax and other similar medicines use to treat osteoporosis?


Thyroid

What is TSH? Why does my doctor say the thyroid is low when TSH is elevated?


I have an overactive thyroid and my doctor recommended a radiation treatment. What is it?


What is the test TSH? Why and when do doctors order this test?


I have gained weight and am having difficulty losing it. Can this be my thyroid?


What are incidentalomas? My partner was found to have a small tumor in her adrenal gland and, after many tests, the doctors told her it was an incidentaloma.


What is Hashimoto's thyroiditis?


What are thyroid nodules?


I have hypothyroidism, and with thyroid pills, I feel better but still feel tired. Is the treatment good?


What is hyperparathyroidism? Why are the calcium levels high in this condition?


Cholesterol

Why do doctors talk about good and bad cholesterol? I thought cholesterol is always bad.

Dr. J. Enrique Silva says:

Cholesterol is an essential substance for the cells' structure and function. 

 

The problem is that excess cholesterol in the body can then accumulate in the blood vessel walls causing a condition called atherosclerosis, wherein vessels are obstructed leading to heart attacks and strokes, among other complications.

 

Cholesterol does not circulate freely in the blood, but in complex particles called lipoproteins. The non-cholesterol part of these particles is in part responsible for the fate of the circulating cholesterol. 

 

In the case of the “bad” cholesterol (LDL cholesterol), these particles deliver the cholesterol to the blood vessel wall favoring atherosclerosis, whereas in the case of “good” cholesterol (HDL cholesterol), the particles draw cholesterol from the blood vessel wall, reducing its accumulation and hence protecting against atherosclerosis.  

 

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Diabetes

My doctor said my diabetes need insulin after years of using pills. Why?

Dr. J. Enrique Silva says:

There are two types of diabetes, Type 1 and Type 2. 

 

  • The former needs insulin at all times since is caused by a destruction of the cells –l ocated in the pancreas - that produce this hormone. 
  • In Type 2 diabetes, these cells are initially able to produce insulin, but sooner or later they may claudicate. 

 

“Pills” used to treat diabetes stimulate insulin production and increase the responses of the body to insulin; that is, they make the patient’s insulin more effective. The time to initiate insulin comes when maximal doses of these pills cannot keep the indexes of diabetes control on target. 

 

Remember that there may be few or no symptoms when diabetes is poorly controlled, but the uncontrolled blood glucose levels are causing damage to virtually all organs and tissue in the body. Do NOT delay the initiation of insulin.  

 

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Why is it important to take good care of the feet in diabetes?

Dr. J. Enrique Silva says:

Diabetes is a condition – particularly if not well controlled - that makes the patient more susceptible to infections.  Diabetes affects large and small blood vessels, reducing the blood flow to tissues, hence hampering their nutrition and barriers against infection.

 

Diabetes also affects nerves causing loss of sensation. Feet are subject to mechanical trauma and vascular and nerve effects of diabetes are more pronounced in legs and feet.  The impaired sensation may cause feet lesions to remain unnoted.  Thus, an otherwise innocent ingrown toenail, a small laceration, wound due to calluses or toenail fungus infection, further enhanced by the slowed healing/repair caused by diabetes, has the potential of becoming serious.

 

Most importantly, all these risks are ameliorated with a good control of the blood glucose (sugar) levels.

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What are Type 1- and Type 2-Diabetes?

Dr. J. Enrique Silva says:

Diabetes is a word that comes from the ancient Greek that means to “pass through”, a term to describe the increased thirst and urination of patients affected by the disease.  Diabetes, without qualifier today, means Diabetes Mellitus (from mellitus = sweet) to indicate that what passes through the body is glucose (the major sugar in the body). 

 

In both Types of Diabetes the central defect is either an absolute (Type 1) or a relative (Type 2) lack of insulin, the hormone produced by the pancreas to regulate the blood glucose level. 

 

In the Type 1 usually becomes evident in childhood or adolescence, when the pancreatic insulin-producing cells are destroyed by self-directed inflammatory process.

 

Type 2 appears later in life. In this condition, the body becomes less responsive to insulin, and the pancreatic insulin-producing cells are forced to produce more insulin.

 

In genetically predisposed individuals, the pancreas sooner or later claudicates and diabetes becomes evident

 

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What is the relationship between obesity and diabetes?

Dr. J. Enrique Silva says:

There are two types of diabetes, called Type 1 and Type 2. Both result ultimately from an absolute (Type1) or a relative (Type 2) lack of insulin.  Insulin is a hormone that controls blood glucose (the main sugar used by the body) levels, so when we eat, insulin diverts glucose to the tissues and reduces production of glucose by the liver. 

 

It is the Type 2 that is frequently associated with obesity. Both obesity and Type 2 Diabetes are very frequent today as a consequence of our life style of overeating and not exercising - that is, they are the consequence of the excess food forced into our bodies and not burned.  Thus, in the overfed condition in which we live today, organs become less responsive to insulin (insulin resistance), in an effort to avoid being “flooded” with glucose.  On the other hand, the body tries to overcome this by producing more insulin. Some individuals, however, probably on a genetic basis, cannot produce sufficient insulin to overcome the resistance and develop Type 2 Diabetes.  

 

Exercising and losing weight have a beneficial effect on diabetes, by increasing glucose oxidation and reducing insulin resistance.

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Why is diabetes treated with pills in some patients while others need insulin?

Dr. J. Enrique Silva says:

It all depends how much insulin can the patient produce. Diabetes is ultimately the result of an absolute or relative lack of insulin. Typically patients with the so-called Type 2 Diabetes can produce some insulin, and many can be treated with pills that can further increase insulin secretion or improve the response of the body to insulin.

 

As time passes, many of these patients cannot produce enough insulin and should be given this hormone in the form of injections.

 

Patients with Type 1 Diabetes completely lack insulin, from the very beginning of the disease and should be treated with injections of insulin.

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Growth Hormone

I read on the Internet that growth hormone could be good for the elderly. Is this an accepted treatment?

Dr. J. Enrique Silva says:

Growth hormone (GH) is produced by the pituitary and is essential to promote growth.

 

Lack of GH is a treatable cause of growth retardation in children.  The hormone has effects that have been considered of potential benefit for elderly, such as stimulation of muscle growth and mobilization of fat stores. 

 

However, there other effects of GH that should be considered in the estimate of the risks of using - among others, the potential to promote or stimulate growth of malignant tumors and to cause insulin resistance. More research is needed before the medical community accepts that the benefits outweigh the risks and is accepted as standard treatment in the adult.  

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Hormones - Acne

Is acne a sign of hormonal imbalance?

Dr. J. Enrique Silva says:

Not necessarily.  Acne results from the stimulation of sebaceous glands of the skin by male hormones, and it may normally occur in boys and girls during puberty. 

 

When severe, and particularly when occurring out of puberty and associated with other problems such as loss or irregularity in menses and hair growth in women, it is likely to be caused by hormonal disorder and it should be investigated. 

 

However, there is a factor of individual susceptibility, so that it may be present in the absence of any detectable hormonal abnormality and vice versa.

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Hormones - Birth Control

Do birth control pills increase weight?

Dr. J. Enrique Silva says:

Birth control pills (BCP) or oral contraceptives contain the hormones produced by the ovaries or synthetic analogs to these hormones.

 

Yes, BCP can be associated with weight gain in some, but not all women.  Modern BCPs are less likely than the older ones to induce weight gains.

 

BCPs with lower estrogen content are less likely to cause weight gain.

 

If a given BCP is suspected to be the cause of weight gain, it is probably wise to change to another pill with less estrogen and with a different progestin.

 

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Hormones - Prolactin

What is prolactin? Doctors say an excess of it caused me to lose my periods.

Dr. J. Enrique Silva says:

Prolactin is hormone produced by the pituitary gland, a small gland in the base of the brain that regulates the function of other endocrine glands. Prolactin is hormone important for the preparation of the mammary (breast) gland for lactation following a pregnancy (prolactin = “pro” “lactation”). 

 

Elevated levels of prolactin during lactation suppress the function of the ovaries, preventing another pregnancy and thus allowing the mother to feed the baby. Small tumors of the pituitary gland frequently produce prolactin in excess, causing the suppression of ovarian activity and the absence of menses, much as during lactation. This is an abnormal condition that requires treatment, which is usually effective.

  

In males, such tumors cause a depression of testicular function. 

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Hormones- Impotence

Is impotence an indication of a "hormonal" problem?

Dr. J. Enrique Silva says:

Impotence or erectile dysfunction, as it is called today, can be caused by hormonal problems but may have many other causes. 

 

Persistent erectile problems should be investigated by your doctor to determine its cause(s). Frequently, the participation of a specialist is necessary. This can be most commonly an endocrinologist or a urologist, but other specialists may be consulted, as dictated by the history of the condition and the presence of other symptoms.

 

Your primary care doctor should do the initial investigation, including certain blood tests, and decide if you need to see and specialist, and if so, which one.

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Menopause

What is menopause?

Dr. J. Enrique Silva says:

Menopause simply means cessation of menses (meno = menses; pause = cessation). 

 

Women in their reproductive years (from puberty to menopause) produce estrogens and progesterone, which feminize their bodies and prepare them for conception and gestation. They are produced in cyclic manner, hence the periodicity of menses.

 

The source of estrogens and progesterone is the ovaries, which have the capacity to produce these hormones for 35-40 years. At the end of this time (age 45-55 in most women), the production declines below the level to support the growth of the lining of the womb (endometrium) and menses (which is the shedding of the endometrium) cease. 

 

The reduction of the ovarian hormones may cause other symptoms, such as reduced energy, sleep abnormalities, sweats and hot flashes. Such symptoms may be alleviated by judiciously prescribing ovarian hormones.  

 

 

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Is it safe to take hormones after menopause?

Dr. J. Enrique Silva says:

This is something that should be assessed individually by your doctor with the aid – if needed - of a specialist.  The menopause is caused by a marked decline of hormone production by the ovaries, and it is frequently associated with a variety of symptoms such as sweats, hot flushes, insomnia.

 

In predisposed women, there could be weakening of the bones, which - when severe - is called osteoporosis.  All these can be alleviated by the administration of estrogens, with or without progesterone, both estrogens and progesterone being the hormones produced by the ovaries. 

 

There are however potential risks of using these hormones. Doctors should individually evaluate the potential benefits against the risks of using these hormones.  

 

 

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Osteoporosis

What is osteoporosis?

Dr. J. Enrique Silva says:

Bones are made of a lattice of organic matter, like interwoven fibers, which is calcified in an organized manner to give them mechanical strength.

 

Osteoporosis is a term to indicate loss of bone mass, a rarefaction of the bone. In this condition, bones become less resistant and brittle. For operational purposes, we define osteopenia as a mild degree of osteoporosis, and osteoporosis a more severe form with clear risk of fractures. 

 

Osteoporosis most commonly results from ageing and the participation of so-called risk factors, such as certain precious or current diseases (e.g. hyperthyroidism, Cushing’s syndrome, and hyperparathyroidism), early menopause, chronic debilitating disease, cancer, smoking and lack of physical activity, among others. There is a strong genetic component in the susceptibility of developing osteoporosis with age.

 

 

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What is bone density or bone densitometry?

Dr. J. Enrique Silva says:

Minerals, specifically calcium salts, contribute to the mechanical resistance of our bones. When we lose bone mass, as in the condition called osteoporosis, the bone density decreases.

 

A practical way to assess the mineral content of the bone is by the absorption of X-rays of a certain energy level as they pass through the bone, which is call densitometry. The higher the mineral content of the bone, the higher will be the absorption of X-rays by the bone, hence the “density”.

 

It should be stressed, though, that the mechanical resistance of bone depends not only on its mineral content, but also its structure - that is, on the amount of cross-linking of the lattice where the mineral is laid.

 

 

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What are Actonel, Fosamax and other similar medicines use to treat osteoporosis?

Dr. J. Enrique Silva says:

These drugs are called generically bisphophonates, based on their chemical structure.

 

Bisphophonates are similar to the chemical form in which phosphorus binds to calcium to form the bones. Bones, contrary to one could think, are dynamic structures, wherein there is active formation and resorption, to allow growth, remodeling and repair.  With age, gradually bone resorption becomes more active than bone formation, and we lose bone mass.

 

Osteoporosis is the condition where this is exaggerated, leading to abnormally fragile bones. Bisphophonates antagonize the activity of the cells involved in bone resorption, and thus slow down the loss of bone and restore in part the mineral content of the bone.    

 

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Thyroid

What is TSH? Why does my doctor say the thyroid is low when TSH is elevated?

Dr. J. Enrique Silva says:

TSH is an acronym for thyroid stimulating hormone, a hormone produced by the pituitary gland on the base of our brain that controls the function of many glands, the thyroid gland among them. There is feedback loop between the thyroid and the pituitary.  This, as a thermostat, senses when the levels of thyroid hormones in blood are below what is needed, and secretes TSH in an attempt to stimulate the thyroid to produce hormones to bring the levels up.

 

The pituitary is very sensitive to changes in thyroid hormone levels, and TSH is nowadays easy to measure. Doctors use TSH to know whether the thyroid is failing or, in the case of patients taking thyroid hormone replacement, to know whether the dose is adequate. If the TSH is elevated, it means the pituitary is sensing suboptimal or low thyroid hormone levels, and the doctor should consider increasing the dose.

 

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I have an overactive thyroid and my doctor recommended a radiation treatment. What is it?

Dr. J. Enrique Silva says:

The “radiation treatment” is a lay term to indicate radioactive iodine treatment. The thyroid gland concentrates iodine, an element necessary to make its hormones. The radioactive iodine produces radiation and since it is concentrated by the thyroid, the same as the natural non-radioactive iodine, the radioactivity can be specifically targeted to the thyroid gland, causing a reduction in the amount of thyroid hormone produced. 

 

It is a safe, simple treatment not requiring admission into the hospital, virtually free of side effects. Unfortunately, the degree of damage to the thyroid gland cannot be regulated, and most patients will develop sooner or later the opposite condition, an underactive thyroid gland. However, the treatment of this condition is simpler and safe.

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What is the test TSH? Why and when do doctors order this test?

Dr. J. Enrique Silva says:

TSH is an acronym for Thyroid Stimulating Hormone. TSH is hormone from the pituitary gland that regulates the function of another gland, the thyroid. The hormones produced by this gland, thyroxin being the major product, regulate the function of most organs of the body. 

 

When the capacity of the thyroid to produce hormones declines, TSH increases in an effort to maintain the production of thyroid hormones. Now, the thyroid gland is frequently a target of chronic autoimmune inflammatory processes akin to some forms of arthritis, fibromyalgia, etc.

 

TSH is thus a way to know whether the capacity of the thyroid to produce its hormones is reduced. In general, the higher the TSH, the worse is the thyroid insufficiency.  The insufficiency of thyroid hormones can cause many symptoms such as lack of energy, somnolence, constipation, memory difficulties, etc. Unfortunately, these symptoms are quite non-specific and derive from a variety of common conditions. A mild elevation of TSH in such cases indicates a thyroid insufficiency may be – but not necessarily is - the culprit.  

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I have gained weight and am having difficulty losing it. Can this be my thyroid?

Dr. J. Enrique Silva says:

Even though patients with hypothyroidism gain some weight, this condition is not the most frequent cause of overweight or obesity.  The hormones from the thyroid gland increase metabolism so, when produced in reduced amounts, metabolism slows down. However, this is associated with less appetite and usually patients with hypothyroidism do not gain much weight.

 

Unexplained weight gain warrants the investigation of hypothyroidism, for which there are accurate tests.  If such tests indicate the thyroid glands functions well, and even if it is slightly slow, other causes for the weight gain should be considered.

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What are incidentalomas? My partner was found to have a small tumor in her adrenal gland and, after many tests, the doctors told her it was an incidentaloma.

Dr. J. Enrique Silva says:

With the rapid progress of technology to visualize our organs for diagnostic purposes, we are incidentally finding tumors in our endocrine glands that otherwise would have remained silent and undiagnosed, and we would have died with them without knowing they were in our body.  This is precisely the definition of an “incidentaloma”. 

 

However, in many occasions these are rather early-diagnosed, medically relevant tumors.  Thus, if a tumor is incidentally found, the challenge for doctors is to decide whether it is of no foreseeable consequences (incidentaloma) or a tumor that could produce hormones or be a cancer, and hence that should be treated. For that reason, such incidentally found tumors should be carefully studied, before concluding that they are “incidentalomas”.  Even if so labeled as “incidentaloma”, the tumor should be followed up.

 

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What is Hashimoto's thyroiditis?

Dr. J. Enrique Silva says:

Hashimoto’s thyroiditis is a chronic inflammation of the thyroid gland which ultimately destroys it, causing hypothyroidism, the name we give to an underactive thyroid gland.  The name of this condition is to honor the Japanese investigator, Dr. Hakaru Hashimoto, who identified and described the disease.

 

The inflammation of the gland is due to autoimmunity or self-directed immunity. The immune system protects us from infections, but in genetically predisposed individuals, the system does not recognize some cells as its own and attacks them as if they were foreign cells, much as an incompatible transplant is rejected from the body.  Many tissues can be affected by autoimmunity, causing different diseases, such as rheumatoid arthritis or vitiligo.

 

The cells of the thyroid gland are frequently the target of autoimmunity.

 

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What are thyroid nodules?

Dr. J. Enrique Silva says:

Thyroid nodules are lumps of tissue that develop in the thyroid gland.  The frequency of these nodules increases with age so that by age 50, about 40 percent of the population has one or more.  The majority are not clinically evident, but its frequency seems to have increased as they are incidentally detected during imaging procedures for other conditions.

 

Over 90 percent are benign lumps of tissue, cysts or benign tumors, but sometimes may represent a thyroid cancer. Once a nodule is diagnosed, it should be studied. This may include ultrasound of neck, scanning and blood tests. The ultimate test is a biopsy done today in the office under ultrasound guidance.

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I have hypothyroidism, and with thyroid pills, I feel better but still feel tired. Is the treatment good?

Dr. J. Enrique Silva says:

Fatigue, tiredness and lack of energy are all symptoms of an underactive thyroid gland. However, these symptoms are quite non-specific, having numerous causes such as excess work, poor sleeping or more serious sleeping disorders, other diseases, etc. 

 

Doctors have tests to ensure the adequacy of the treatment.  Once verified that the dose of thyroid hormone (generically called thyroxin) is adequate, the doctor should look for other explanations for the persistence of symptoms, such as those mentioned above.

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What is hyperparathyroidism? Why are the calcium levels high in this condition?

Dr. J. Enrique Silva says:

The parathyroid glands are four each, weighing around 30 mg each. Their name derive from being right behind the thyroid gland, in the neck (para = beside).  These little glands control the calcium level in the blood, via its secretion, the parathyroid hormone (PTH) which works on the bone and the kidney. 

 

Hyperparathyroidism is the condition wherein one or more of these glands produces an excess of PTH.  This mobilizes calcium from the bones and reduces the clearance of calcium by the kidney.  The concentration of calcium in blood increases, which is called hypercalcemia in medical terminology.  

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