An article in the Air Force Times by Allison Pattillo used advise from Andrea Lindsey, senior nutritionist at the military’s Human Performance Resource Center, on caffeine, conjugated linoleic acid (CLA), and green tea “to separate the helpful from the hype,” as Pattillo put it.
Caffeine, is commonly used as a stimulant and marketing claims say it provides appetite suppression and increased fat burning. Research has shown drinking caffeinated coffee or tea may slightly boost weight loss or prevent weight gain, but they said no evidence suggests increased caffeine consumption will result in significant or permanent weight loss. They recommend taking less than 600 mg a day in pill form, beverages and gum, and note a 12-ounce (tall) regular Starbucks coffee contains about 260 mg of caffeine. They warn that while caffeine is GRAS (generally recognized as safe), doses greater than 600 mg may be unsafe and can cause insomnia, nervousness, restlessness, stomach irritation, nausea, vomiting, increased heart rate, tolerance, habituation and psychological dependence.
CLA may reduce body-fat mass, according to some studies, but they write it has shown only a minimal effect on body weight or body mass index (BMI). CLA can come in pill form and also occurs naturally in foods such as milk, cheese, beef and lamb, and an effective dose comes in the range of 1.8 to 7 g per day for weight loss in obese patients. The most common side effects, they write, are upset stomach, diarrhea, nausea and fatigue.
Green tea contains 2 percent to 4 percent caffeine per cup, which certainly helps its position as a weight-loss product, but it also is known to improve mental clarity and to treat stomach disorders. The flavonoids and polyphenol epigallocatechin gallat (EGCG) also help boost its healthy supplement status. However, Pattillo and Lindsey said the research is mixed and more studies are needed. The combination of green tea and caffeine has shown to decrease BMI and increase weight loss. As a beverage, the dose range is large, from one to 10 cups each day, but they note three cups has 240 mg to 320 mg of the active polyphenols. The side effects here include nausea, vomiting, abdominal bloating, pain and diarrhea; more than five cups per day may cause additional adverse side effects caused by the caffeine, they wrote.