ThyroSupport by Dr. Garber's

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Alzheimer disease. Although there has been interest in using oral black currant berry for Alzheimer disease, there is insufficient reliable information about the clinical effects of black currant for this purpose.
• Atopic dermatitis (eczema). Topical black currant seed oil has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in children aged 2-18 years with atopic dermatitis shows that using a specific cream containing black currant seed oil, sunflower oil, and balloon vine (Defensil), with added dexpanthenol and ceramide, twice daily for 4 weeks, improves atopic dermatitis severity scores similarly to urea 5% cream. About 38% of patients had a 50% improvement in severity score with the combination cream, compared with 35% with urea cream (105538).
• Colic. Although there has been interest in using oral black currant leaf for colic, there is insufficient reliable information about the clinical effects of black currant for this purpose.
• Common cold. Although there has been interest in using oral black currant berry for common cold, there is insufficient reliable information about the clinical effects of black currant for this purpose.
• Cough. Although there has been interest in using oral black currant leaf for cough, there is insufficient reliable information about the clinical effects of black currant for this purpose.
• Diarrhea. Although there has been interest in using oral black currant leaf for diarrhea, there is insufficient reliable information about the clinical effects of black currant for this purpose.
• Dry eye. Oral black currant has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Clinical research in adults with dry eye disease shows that taking a specific combination product containing black currant 100 mg, L-carnitine 50 mg, elderberry fruit extract 300 mg, zinc 10 mg, and Eleutherococcus root 50 mg (Meramirt CM) orally once daily improves dry eye symptom scores when compared with no intervention. Contrast sensitivity scores also improved when compared with baseline in the treated group, but not in the control group (111295). It is unclear if this effect is due to black currant, other ingredients, or the combination.
• Dysmenorrhea. Although there has been interest in using oral black currant seed oil for dysmenorrhea, there is insufficient reliable information about the clinical effects of black currant for this purpose.
• Glaucoma. It is unclear if oral black currant is beneficial in patients with glaucoma. Details: Preliminary clinical research in adults with glaucoma shows that taking black currant anthocyanins 50 mg orally daily for 4 weeks decreases intraocular pressure (IOP) by 1.5 mmHg when compared with placebo (93696). However, other preliminary clinical research in patients with open-angle glaucoma shows that taking black currant anthocyanins 50 mg orally daily along with standard medications for glaucoma for 24 months does not improve IOP when compared with placebo (93695). Preliminary subgroup analyses suggest that patients taking one or less antiglaucoma medications, but not more than one, may benefit the most from black currant (93695,93696).
• Gout. Although there has been interest in using oral black currant leaf for gout, there is insufficient reliable information about the clinical effects of black currant for this purpose.
• Hyperlipidemia. It is unclear if oral black currant seed oil is beneficial in patients with hyperlipidemia. Details: Preliminary clinical research in adults with hyperlipidemia shows that taking black currant seed oil 18 grams orally twice daily for 6 weeks reduces total cholesterol by about 16%, reduces triglycerides by about 34%, and increases high-density lipoprotein (HDL) cholesterol by about 35% when compared with baseline (17638). However, the validity of this study is limited by the lack of a comparator group.
• Hypertension. It is unclear if oral black currant seed oil is beneficial in patients with hypertension. Details: Preliminary clinical research in males with borderline hypertension shows that taking black currant seed oil 6 grams orally daily for 8 weeks does not reduce blood pressure when compared with safflower oil 6 grams daily. However, when stress is induced by a mental arithmetic exercise, black currant seed oil appears to induce a 40% reduction in systolic and diastolic blood pressure elevations in these patients (35994).
• Influenza. Although there has been interest in using oral black currant berry for influenza, there is insufficient reliable information about the clinical effects of black currant for this purpose.
• Insect bite. Although there has been interest in using topical black currant leaf for insect bite, there is insufficient reliable information about the clinical effects of black currant for this purpose.
• Japanese cedar pollinosis. It is unclear if oral black currant extract is beneficial in patients with Japanese cedar pollinosis. Details: Preliminary clinical research in patients with Japanese cedar pollinosis shows that taking a black currant polysaccharide extract 540 mg orally twice daily for 8 weeks does not improve nasal symptom scores or swelling when compared with placebo (17635).
• Liver disease. Although there has been interest in using oral black currant leaf for liver disease, there is insufficient reliable information about the clinical effects of black currant for this purpose.
• Menopausal symptoms. Although there has been interest in using oral black currant seed oil for menopausal symptoms, there is insufficient reliable information about the clinical effects of black currant for this purpose.
• Muscle fatigue. It is unclear if oral black currant juice extract is beneficial in patients with muscle fatigue. Details: Preliminary clinical research in office workers shows that black currant juice extract, containing 10.83% anthocyanins, taken once orally and dosed as anthocyanins 17 mg/kg, reduces muscle stiffness scores after typing for 30 minutes when compared with placebo (17633).
• Osteoarthritis. Although there has been interest in using oral black currant leaf for osteoarthritis, there is insufficient reliable information about the clinical effects of black currant for this purpose.
• Peripheral arterial disease (PAD). Although there has been interest in using oral black currant juice for PAD, there is insufficient reliable information about the clinical effects of black currant for this purpose.
• Premenstrual syndrome (PMS). Although there has been interest in using oral black currant seed oil for PMS, there is insufficient reliable information about the clinical effects of black currant for this purpose.
• Rheumatoid arthritis (RA). It is unclear if oral black currant seed oil is beneficial in patients with RA. Details: A small clinical study in patients with RA shows that taking black currant seed oil 10.5 grams orally daily for 24 weeks reduces tenderness scores when compared with placebo (35990).
• Rhinosinusitis. Oral black currant has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: A small clinical study in patients over 12 years of age with chronic sinusitis shows that taking a combination product containing black currant, Boswellia serrata, bromelain, and vitamin D (Flogostop Forte, Humana Italia) with inhaled corticosteroids daily for 30 days reduces rhinorrhea, hyperemia of mucosa, and local inflammation when compared with inhaled corticosteroids alone (111501). It is unclear if these findings are due to black currant, other ingredients, or the combination.
• Seizures. Although there has been interest in using oral black currant leaf for seizures, there is insufficient reliable information about the clinical effects of black currant for this purpose.
• Upper respiratory tract infection (URTI). Although there has been interest in using oral black currant berry for URTIs, there is insufficient reliable information about the clinical effects of black currant for this purpose.
• Urinary tract infections (UTIs). Although there has been interest in using oral black currant leaf for UTIs, there is insufficient reliable information about the clinical effects of black currant for this purpose.
• Venous insufficiency. Although there has been interest in using oral black currant for venous insufficiency, there is insufficient reliable information about the clinical effects of black currant for this purpose.
• Wound healing. Although there has been interest in using topical black currant leaf for wound healing, there is insufficient reliable information about the clinical effects of black currant for this purpose. More evidence is needed to rate black currant for these uses.

(Read more about BLACK CURRANT)

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Aging skin. It is unclear if oral sweet almond is beneficial in patients with aging skin. Details: Preliminary clinical research in postmenopausal females shows that consuming sweet almonds as 20% of daily energy intake for 16 weeks reduces wrinkle severity scores by approximately 8% when compared with consuming a calorie-matched snack (101756).
• Atopic dermatitis (eczema). Topical sweet almond oil has only been evaluated in combination with other ingredients; its effect when used alone is unclear. Details: Preliminary clinical research in patients with xerotic eczema shows that applying an emollient containing lactic acid 5% and refined sweet almond oil 10%, with or without polidocanol 5%, twice daily (Antidry Lotion or Antidry Calm) for 2 weeks reduces itching by up to 69% when compared with baseline. Benefits occurred within 30 minutes of the first use and seemed to be related to improved moisture and lipid content of the skin (101788).
• Attention deficit-hyperactivity disorder (ADHD). It is unclear if oral sweet almond extract is beneficial in patients with ADHD. Details: Preliminary clinical research in children aged 6-14 years old with ADHD shows that taking sweet almond extract syrup, 5 mL three times daily, for 8 weeks does not affect parent- or teacher-rated hyperactivity or inattention scores when compared with methylphenidate 1 mg/kg orally daily. This study may have been inadequately powered to detect a difference between groups (101783).
• Cancer. Although there has been interest in using oral sweet almond for cancer, there is insufficient reliable information about the clinical effects of sweet almond for this purpose.
• Cardiovascular disease (CVD). Although there has been interest in using oral sweet almond for CVD, there is insufficient reliable information about the clinical effects of sweet almond for this purpose.
• Coronary heart disease (CHD). It is unclear if oral sweet almond is beneficial for the prevention or treatment of CHD. Details: A small clinical trial in patients with hypercholesterolemia has found that intake of sweet almonds for 4 weeks is associated with decreased CHD risk based on the Framingham 10-year risk score. Each 30-gram intake of sweet almonds was associated with an estimated 3.5% decrease in risk scores (99940). In 2003, the US Food and Drug Administration (FDA) determined that it would allow a qualified health claim stating that consuming 1.5 ounces of almonds per day, as part of a diet low in saturated fat and cholesterol, may reduce the risk of CHD. However, the FDA has concluded that this claim is based on supporting, rather than conclusive, evidence (102331). It is unclear if sweet almonds improve outcomes in patients with CHD. Preliminary clinical research in adults with CHD shows that incorporating sweet almonds 85 grams daily into a National Cholesterol Education Program (NCEP) Step I diet for 6 weeks does not improve total or low-density lipoprotein (LDL) cholesterol, blood pressure, vascular function, or inflammatory markers when compared to the NCEP Step 1 diet without sweet almonds (99938). However, the short duration of this study limits the validity of the findings.
• Constipation. It is unclear if oral or topical sweet almond is beneficial in patients with constipation. Details: A small single-blinded clinical study in older adults with constipation shows that taking sweet almond oil 9 mL twice daily or abdominal massage with 18 mL of sweet almond oil every other day for 2 weeks both independently improve symptoms of constipation, stool consistency, and quality of life when compared with no treatment. Improvement in constipation and quality of life were also superior with oral sweet almond oil over sweet almond oil massage (111392). The validity of these findings is limited by a lack of placebo control.
• Diabetes. It is unclear if oral sweet almond is beneficial in patients with diabetes. Details: Research on whether sweet almond improves glycemic control in patients with diabetes is conflicting. A small study in patients with type 2 diabetes and mild hyperlipidemia shows that consuming sweet almonds as 20% of energy intake (approximately 60 grams daily) as part of a National Cholesterol Education Program (NCEP) Step II diet for 4 weeks, along with hypoglycemic medications, improves measures of glycemic control, as well as lipids and adiposity. Fasting insulin and glucose levels decreased by 4% and 1%, respectively, when compared with the diet without sweet almonds. Also, low-density lipoprotein (LDL) cholesterol levels were reduced by about 12% (99941). Preliminary clinical research also shows that regularly consuming sweet almonds as part of a low-carbohydrate diet for 12 weeks is more effective than consuming cheese, but no more effective than peanuts, for reducing glycated hemoglobin (HbA1c) levels (99943,101787). However, the change in HbA1c demonstrated in these small trials may not be considered clinically relevant. In contrast, meta-analyses of many clinical trials in patients with a variety of metabolic disorders, including diabetes, shows that eating almonds 5-85 grams daily, or as 10% to 20% of energy, for 4-24 weeks does not improve fasting blood glucose levels, HbA1c, insulin levels, or measures of insulin resistance when compared with control (109019,111395).
• Hyperlipidemia. Small clinical studies suggest that oral sweet almond might reduce total cholesterol and low-density lipoprotein (LDL) cholesterol in patients with hyperlipidemia, but it does not appear to improve other lipid levels in these patients. Details: Several small clinical studies in adults with hyperlipidemia show that consuming raw sweet almonds 42.5-100 grams or taking sweet almond oil 10 mL daily for 4-9 weeks reduces low-density lipoprotein (LDL) cholesterol levels by 3% to 15% when compared with control diets or baseline levels. Most of these studies failed to show improvements in high-density lipoprotein (HDL) cholesterol levels or triglyceride levels when compared with control (76725,76737,99939,101786), although one study showed a 4% improvement in HDL levels (99940). A meta-analysis of 8 clinical trials in patients with hyperlipidemia or in which at least half of the patients were classified as having hyperlipidemia shows that consuming sweet almonds or taking sweet almond oil daily for 4-12 weeks modestly reduces total cholesterol and LDL cholesterol but does not improve very low-density lipoprotein (VLDL) cholesterol, triglycerides, or HDL cholesterol when compared with placebo or no treatment (111395).
• Hypertension. It is unclear if oral sweet almond is beneficial in patients with hypertension. Details: A meta-analysis of 10 small clinical studies in which at least half of the patients in each study were classified as having hypertension at baseline shows that taking sweet almond does not improve systolic or diastolic blood pressure when compared with placebo or no treatment (111395). The validity of these findings is limited by a high degree of heterogeneity across the studies.
• Insomnia. It is unclear if oral sweet almond is beneficial in patients with insomnia. Details: Preliminary clinical research in students shows that consuming ten sweet almonds daily for 2 weeks reduces the percentage of students reporting insomnia on sleep surveys from 78% to 69% (101784). The validity of this study is limited by the lack of a control group.
• Impaired glucose tolerance (prediabetes). It is unclear if oral sweet almond is beneficial in patients with prediabetes. Details: A small clinical study in adults with prediabetes shows that consuming 20 grams of sweet almonds 30 minutes before breakfast, lunch, and dinner daily for 3 months reduces fasting blood glucose and glycated hemoglobin (HbA1c) by 6 mg/dL and 0.4%, respectively, and improves measures of insulin resistance when compared with a control group. For every 4 patients consuming sweet almonds, one additional patient experienced normalization of HbA1c. Body weight, body mass index (BMI), total cholesterol, and low-density lipoprotein (LDL) cholesterol were also improved with sweet almond over control (111389).
• Irritable bowel syndrome (IBS). It is unclear if oral sweet almond flour is beneficial in patients with IBS. Details: Preliminary clinical research in patients with diarrhea-predominant IBS shows that taking sweet almond flour 40 grams orally daily for 20 days does not improve IBS symptom scores when compared with a wheat flour placebo. In fact, those taking sweet almond flour experienced an increase in severity of pain and the number of bowel movements (101785).
• Obesity. It is unclear if oral sweet almond is beneficial in patients with obesity. Details: A moderate-sized clinical study in adults with overweight and obesity shows that consuming 30-50 grams of sweet almonds does not reduce self-reported appetite ratings or subsequent short-term energy intake despite favorable changes in appetite-regulating hormones when compared with a carbohydrate-rich snack as a control (111388). Other preliminary clinical research in adults with overweight or obesity shows that following a calorie-restricted diet with almonds as 15% of total daily energy for 12 weeks increases fat loss by 2.4-fold, but does not affect total weight loss, when compared with a nut-free, calorie-restricted diet (99937). Another preliminary clinical study in mainly overweight individuals shows that consuming sweet almonds 56 grams daily for 4 weeks in addition to the regular diet reduces levels of total and low-density lipoprotein (LDL) cholesterol by approximately 5% when compared with eating isocaloric cookies. However, there was no effect on body weight, body composition, glycemic control, or blood pressure (101790).
• Psoriasis. Although there has been interest in using topical sweet almond oil for psoriasis, there is insufficient reliable information about the clinical effects of sweet almond for this purpose.
• Radiation dermatitis. It is unclear if topical sweet almond ointment is beneficial in patients with radiation dermatitis. Details: Preliminary clinical research in females receiving radiation therapy for breast cancer shows that topical use of a sweet almond ointment once before each treatment and once a few hours after each treatment does not prevent radiation dermatitis when compared with chamomile extract cream (76740).
• Stretch marks (striae gravidarum). It is unclear if topical sweet almond oil is beneficial in patients with stretch marks. Details: Preliminary clinical research in nulliparous patients shows that topical application of sweet almond oil twice daily, starting at gestational week 16 and continued until delivery, does not reduce the size or number of stretch marks when compared with control. However, using the sweet almond oil modestly reduced itching scores (97322). More evidence is needed to rate sweet almond for these uses.

(Read more about SWEET ALMOND)

INSUFFICIENT RELIABLE EVIDENCE to RATE

• Hypothyroidism. Although there has been interest in using oral thyroid extract for hypothyroidism, there is insufficient reliable information about the clinical effects of thyroid extract for this purpose.
• Infertility. It is unclear if oral thyroid extract is beneficial in females with infertility. Details: A small clinical study in female patients with infertility caused by luteal-phase deficiency shows that taking a specific thyroid extract (Thyranon) 25 mg daily to start, and then doubling the dose every 2 weeks to a maximum 100 mg daily, for three menstrual cycles increases pregnancy rate when compared with placebo. Of the patients receiving thyroid extract, 8 out of 17 became pregnant by the fourth month, while only 1 out of 7 patients in the placebo group became pregnant (28618).
• Thyroid cancer. Although there has been interest in using oral thyroid extract after treatment for thyroid cancer, there is insufficient reliable information about the clinical effects of thyroid extract for this purpose. More evidence is needed to rate thyroid extract for these uses.

(Read more about THYROID EXTRACT)

LIKELY SAFE ...when used orally and appropriately. Black currant juice, leaves, and flowers have Generally Recognized As Safe (GRAS) status in the US (4912). Black currant juice up to 3000 mL daily for up to 3 weeks (17636,35987), black currant extracts 1080 mg daily for 8 weeks (17635,93695), and black currant seed oil products up to 10.5 grams daily for 24 weeks (4016,17634,17638,35990) have also been used safely in clinical research. There is insufficient reliable information about the safety of black currant when used topically.

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.

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LIKELY SAFE ...when used in amounts commonly found in foods. Sweet almond is commonly eaten as a food (99937,99938,99939,99941). There is insufficient reliable information available about the safety of sweet almond when used orally or topically in medicinal amounts.

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using in amounts greater than those commonly found in foods.

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POSSIBLY UNSAFE ...when taken orally. Thyroid extract contains triiodothyronine (T3) and thyroxine (T4) (29981). However, the potency of these hormones varies, making dose titration difficult (29982,29983,29984,109614). Using thyroid extract increases the risk of hyperthyroidism and associated cardiac and neurological complications (28621,29987,97621).

PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.

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ANTICOAGULANT/ANTIPLATELET DRUGS Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, black currant seed oil might increase the risk of bleeding if used in combination with anticoagulant or antiplatelet drugs.  Details Gamma-linolenic acid (GLA), a constituent of black currant seed oil, appears to have antiplatelet effects (1979,35995).

PHENOTHIAZINES Interaction Rating = Moderate Be cautious with this combination. Severity = High •  Occurrence = Possible •  Level of Evidence = D Theoretically, black currant seed oil might increase the risk of seizure in patients receiving phenothiazines.  Details Black currant seed oil contains gamma-linolenic acid (GLA). There is some concern that taking supplements containing GLA might cause seizures, or lower the seizure threshold, when taken with phenothiazines, although there is no evidence that black currant seed oil causes seizures (88187). In one report, three patients with schizophrenia who had received phenothiazines developed EEG changes suggestive of temporal lobe epilepsy after starting treatment with GLA, although none experienced an actual seizure (21013). In another report, two patients with schizophrenia who were stabilized on phenothiazines developed seizures when evening primrose 4 grams daily, which contains GLA, was added. One of these patients had a prior history of seizures (21010).

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LEVOTHYROXINE (Synthroid, others) Interaction Rating = Moderate Be cautious with this combination. Severity = Moderate •  Occurrence = Possible •  Level of Evidence = D Theoretically, thyroid extract might increase the effects and adverse effects of levothyroxine.  Details Thyroid extract contains triiodothyronine (T3) and thyroxine (T4) (29981,97621). Taking thyroid extract increases blood levels of T3 and T4, in some cases to abnormally high levels (28621,29987,97621).

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General ...Orally, black currant is generally well-tolerated. Topically, there is a limited amount of information on the adverse effects of black currant.

Gastrointestinal ...Of 2154 patients with hyperlipidemia taking black currant seed oil 1. 8 grams twice daily for 6 weeks, 8 reports of mild diarrhea were considered related to the supplement. These adverse reactions were reported 2-10 days after beginning treatment with black currant seed oil (17638).

(Read more about BLACK CURRANT)

General ...Orally, when consumed as food, sweet almond is well tolerated. Orally and topically, when used as medicine, adverse effects from sweet almond seem to be rare; however, a thorough safety evaluation has not been conducted.
Most Common Adverse Effects:
Orally: Allergic reactions.
Topically: Dermatitis, itching.

Dermatologic ...Topically, itching, dermatitis, and worsening eczema have been reported in a clinical trial (101788).

Immunologic ...Tree nuts, which include almonds, can cause allergic reactions in sensitive individuals. Due to the prevalence of this allergy in the general population, tree nuts are classified as a major food allergen in the United States (105410).

Neurologic/CNS ...Orally, adverse effects to sweet almond extract in syrup have included increased sleep (101783).

Other ...Orally, adverse effects to sweet almond extract in syrup have included increased appetite (101783).

(Read more about SWEET ALMOND)

General ...Orally, thyroid extract may be unsafe due to hormone potency inconsistencies.
Most Common Adverse Effects:
Orally: Elevated levels of triiodothyronine (T3) and/or thyroxine (T4).
Serious Adverse Effects (Rare):
Orally: Thyroid storm or thyrotoxic crisis.

Dermatologic ...In one case report, a teenage female taking thyroid extract developed multiple nevi on the skin (28622). In another case report, a 30-year-old female with allergic rhinitis and multinodular goiter developed allergic urticaria after treatment with desiccated thyroid extract (28619).

Endocrine ...Clinical research shows that many patients treated with thyroid extract experience abnormally high levels of triiodothyronine (T3) and/or thyroxine (T4) (28621,29987,97621). In some patients, these elevated hormone levels result in thyrotoxic crisis or thyroid storm, with symptoms including nausea, vomiting, myalgia, fever, tachycardia, hypertension, agitation, and altered mental state (28621,29987,97621). In one case, a healthy 62-year-old female took a thyroid extract that was accidentally compounded to provide T3 and T4 at levels of 720,000 and 30,000 micrograms, respectively, daily. The patient required plasmapheresis for two days to reduce levels of T3 and T4 and reduce the symptoms of thyroid storm (97621).

Immunologic ...A 30-year-old female with allergic rhinitis and multinodular goiter developed allergic urticaria after treatment with desiccated thyroid extract (28619).

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