Whether somewhere on the internet, at the gym, or in a supplement store, I'm sure you've heard someone raving about their BCAA supplement. But what does science say about the usefulness of BCAAs?
Well first, lets talk briefly about what BCAAs are.
Protein is made up of amino acids. BCAA stands for branched chain amino acids. There are 9 essential amino acids, but BCAA refers to the three amino acids, leucine, isoleucine, and valine.
Since your body cannot produce BCAAs on its own, yes, you do need to consume them; HOWEVER, that does not mean you need to purchase supplements. BCAAs are found in foods such as chicken, fish, eggs, lentils... pretty much most protein sources. As long as you're getting adequate protein, you're getting enough BCAAs.
So you may be thinking, "what if I don't get adequate protein?" My suggestion for that is to supplement with whey protein. Whey protein provides all 9 essential amino acids, therefore, would be the more optimal choice [1.].
What about the other benefits of BCAA powders though?
The other fabulous things you've heard that BCAA supplement powders can do are probably false or exaggerated..
1. Some people think they are useful while fasted or while doing fasted training. Sorry, but they aren't. Many people who do Intermittent Fasting believe they are going to lose muscle if they don't take BCAAs. Skipping a meal isn't going to kill your gains. Again, get in your protein in your eating window and you will be fine- No BCAAs necessary. Whether you train fasted or not makes no difference in body composition; you still don't need the BCAAs. [2,3,6,7}
2. Oh, by the way, if you are supplementing with BCAAs, you aren't fasting. For some odd reason, it is believed that BCAAs are calorie free, which is NOT the case. So for those of who chug these gallon jugs with BCAAs while "fasted"... yea, you're not fasted. BCAAs actually have around 6 calories per gram . So for one scoop of BCAA powder, you're consuming approximately 60 calories (even though your nutrition label most likely says 0, or negligible calories). Loopholes in the FDA regulations allow manufacturers to list BCAAs as zero calories .
3. Another reason some people take them is because they believe taking them while training is beneficial and can improve performance. There is no scientific evidence that supports this claim. BCAA supplementation does not increase performance, strength, or athletic ability in any way. [6,8,9]
4.. A lot of people take BCAAs thinking it will cause fat loss, while some think it will promote extra muscle growth. The only way to lose fat is with a caloric deficit. Ingesting additional calories isn't going to magically make you lose extra fat. To build muscle, yes protein plays a major role; but science does not support the claim that BCAAs increase or speed up muscle gain. [7,10,11]
The Bottom Line
To put it simply just consume adequate protein daily. If you need to supplement to get sufficient protein, use a complete source such as whey. Science says there is no added benefit to taking a BCAA supplement when you hit your protein goal. Save that money and use towards your grocery bill.
When trying to lose weight, you may come across a lot of information online or from friends telling you the "fastest and best" way to lose weight and get shredded. They'll say "x" method is better and burns more fat or that you must eat "x" to lose weight.
But which information is useful and which isn't? Sometimes having too much info can be confusing and overwhelming. Since it can be difficult to weed out unnecessary information, I'll tell you right here what you can ignore and why.
1. "Do fasted cardio. It burns more fat!"
No. It. Does. Not. Fasted cardio does not burn more fat nor is it more advantageous than fed cardio. There is nothing wrong with performing fasted cardio; I like fasted cardio personally. However, there is no research that concludes it is better. Some people have better performance and a more intense workout when they are fed. If this is the case and you feel worse working out fasted, you may actually expend fewer calories by doing so. For this reason, it IS recommended to do cardio whichever way your prefer: fasted or fed. 
2. "You should cut out carbs because they make you fat."
Cutting out carbs is completely unnecessary. Carbs do not make you fat, excess calories do . If you are eating in a caloric deficit, you will lose fat whether your carbs are low or high. There is no possible way you will gain fat, in a caloric deficit. That would defy the Laws of Thermodynamics. Low carb will not cause any faster or additional fat loss . If low carb is your preference, then by all means, go for it. But if the thought of giving up carbs makes you cringe, then don't. Stick to a caloric deficit, get enough protein, and you will progress. It's unnecessary to restrict specific foods. It's the quantity of food that matters. You can gain weight eating low carb, or even eating only "clean" foods if you're eating too much. A sustainable plan is best because adherence and consistency is what produces results. I prefer a flexible dieting approach. You can get your macros to start flexible dieting, or IIFYM, here.
3. "Try to keep your insulin low. If it spikes, you can't burn fat!"
This is so false, it makes me cringe. Your body only stores fat in a caloric surplus. If you eat in a caloric deficit, you will lose fat regardless of insulin levels . One can have low levels of insulin and gain fat or high levels of insulin and lose fat. Insulin does not inhibit fat burning. Your insulin will pretty much spike any time you eat. Most people know that carbs will spike insulin, but protein is actually responsible for higher insulin levels. People will recommend eating foods lower on the Glycemic Index , but it's really irrelevant. Deficit = weight loss.
4. "You should carb cycle, it'll really shred fat!"
While you can effectively lose fat while carb cycling, it isn't a necessity. It won't speed up fat loss. Carb cycling may be beneficial for those who want to eat more on training days and don't mind eating less on rest days. For beginners, carb cycling may be confusing and frustrating. Some people may enjoy a more simplistic, yet effective approach, You can achieve the same results with consistent macros that don't cycle. How, you ask? Well if you keep macros the same, lets say you eat 200g daily, then at the end of the week you will have eaten 1400g of carbs. Now lets say you carb cycle and eat 300g three times a week, 100g three times a week, and 200g once a week. That's still 1400g carbs per week. This is why results will be the same. Either way works, so do what you prefer.
5. "Eat this, take this- it'll burn belly fat!"
Sorry, no specific food or pill will target and burn fat. Also detoxes are scams (unless you don't have a functioning liver) and do not cause weight loss . Not much else to say in regards to that...
6. "You should eat every 3 hours to speed up your metabolism."
Your metabolism doesn't work that way. Meal timing or meal frequency over the course of a day isn't going to change your metabolism. It does not matter if you eat once a day or six times a day. Eating more often will not induce additional fat burning or faster metabolism. This is why people are able to lose weight while doing intermittent fasting. 
To achieve weight loss, the following should be your primary focus:
a. Eat less calories than you burn. About 20-25% below your TDEE (total daily energy expenditure) is sufficient.
b. Exercise. Do you have to exercise to lose weight? No. But you should. Great for your health and will help achieve your physique goals.
c. Move more often. Take the stairs, take your kids to the park, walk on your lunch break. This will help burn a few more calories through the day.
There's really no other tricks or secrets to weight loss. Just have to be consistent in your efforts and the results will come.
1. Schoenfeld, B. J., Aragon, A. A., Wilborn, C. D., Krieger, J. W., & Sonmez, G. T. (2014). Body composition changes associated with fasted versus non-fasted aerobic exercise. Journal of the International Society of Sports Nutrition, 11, 54. http://doi.org/10.1186/s12970-014-0054-7
2. Strasser, B., Spreitzer, A., & Haber, P. (2007). Fat loss depends on energy deficit only, independently of the method for weight loss. Annals of Nutrition and Metabolism, 51(5), 428-432.
3. Sacks, F. M., Bray, G. A., Carey, V. J., Smith, S. R., Ryan, D. H., Anton, S. D., … Williamson, D. A. (2009). Comparison of Weight-Loss Diets with Different Compositions of Fat, Protein, and Carbohydrates. The New England Journal of Medicine, 360(9), 859–873. http://doi.org/10.1056/NEJMoa0804748
5. Raatz, S. K., Torkelson, C. J., Redmon, J. B., Reck, K. P., Kwong, C. A., Swanson, J. E., ... & Bantle, J. P. (2005). Reduced glycemic index and glycemic load diets do not increase the effects of energy restriction on weight loss and insulin sensitivity in obese men and women. The Journal of nutrition, 135(10), 2387-2391.
7. Bellisle, F., McDevitt, R. and Prentice, A.M. (1997) ‘Meal frequency and energy balance’, British Journal of Nutrition, 77(S1), pp. S57–S70. doi: 10.1079/BJN19970104.
Arielle is a certified fitness trainer, certified sports nutritionist, fitness enthusiast, and bikini competitor who has been involved in fitness since 2011. She also is studying for her Doctorate of Health Science in Nutrition and Exercise Science.