Appetite Out of Control? Phenylalanine May Be the Answer!

Okay, you’ve decided to lose weight and take charge of your health. But how do you deal with those late night snack attacks and mid-afternoon cravings for candy, cookies, soda, and chips?

If you’re really serious about taking charge of your appetite and are tired of battling your cravings and added pounds, here’s a safe way to manage your eating habits and finally get your weight under control!

What is phenylalanine?

Phenylalanine is an essential amino acid that acts as an appetite suppressant by administrating the release of an intestinal hormone—cholecystokinin—which signals the brain to feel satiated after eating.

Here’s how appetite control works: cholecystokinin (CCK) is released as food enters the stomach. It tells the digestion to slow down and then gives the message to the brain that you are ‘full’ . . . so your appetite naturally decreases. This takes time—usually around 20 minutes.

Phenylalanine is found in a variety of foods, including almonds, avocados, bananas, brown rice, cheese, corn, eggs, fish, lima beans, peanuts, pumpkin seeds, sesame seeds, and soy products. Problem is, you’d have to eat lots of extra calories in order to get an efficacious amount.

That’s why phenylalanine is sold as a convenient nutritional supplement.

If you take phenylalanine 30 minutes to one hour before eating a meal, you’ll notice that you’ll feel full faster—so you don’t fill up on extra calories that you don’t need! And not only that, you’ll stay full longer so you don’t get that late afternoon or after-dinner snack attack. Before you know it, those extra pounds you’ve been carrying around will start to melt away—safely and effortlessly.

Phenylalanine study

L-Phenylalanine’s ability to suppress appetite by stimulating the production of the appetite-suppressing hormone, cholecystokinin, was proven in a laboratory study with rhesus monkeys. In the first test, the monkeys were given cholecystokinin intravenously after having been deprived of food overnight. Sure enough, the monkey’s appetites were suppressed. In the second test, the monkeys again weren’t allowed to eat anything during the night previous to testing. Even though they were hungry, after they were given phenylalanine, the monkeys’ appetite was suppressed. The test indicates that phenylalanine helps release cholecystokinin, the hormone that suppresses appetite.

Boosts mood

According to Priscilla Slagle, M.D., author of The Way Up From Down, “Diet changes and natural supplements can alter your brain chemistry so that you can think and perceive positively.”

With L-Phenylalanine, Caffeine & Taurine

Three forms of phenylalanine

Phenylalanine, along with two other amino acids, tyrosine and methionine, helps the body produce adrenaline. It is also a precursor for other proteins and enzymes, including norepinephrine, epinephrine, and dopamine. It is available in three different forms: L, D, and DL. The L form is the most common and is the type which is incorporated into your body’s proteins. The D form acts as a painkiller, and the DL is a combination of the two.

  1. D-Phenylalanine—one of the three forms of phenylalanine—increases endorphins, your natural pain relievers, thus aiding in pain relief and mood elevation. It has been found to be safer than and as effective as commonly prescribed and/or over-the-counter drugs.12 It can help alleviate stubborn pain as well as depression, offering hope to individuals who had formerly been despondent about chronic situations.
  2. L-Phenylalanine converts to phenylethylamine, an amphetamine-like stimulatory compound and also converts to norepinephrine and dopamine (via tyrosine) which are mood elevating, motivating, stress protective body chemicals.
  3. DL-Phenylalanine (DLPA) is a combination of L-phenylalanine and D-phenylalanine. DLPA has also been found to be beneficial in combating depression, elevating mood, producing a feeling of satiety, and boosting the body’s natural pain-killing response.

So, if you want to control your appetite, lose weight painlessly, and maintain a good mood, try L-phenylalanine!

Lose weight and stay positive!

Once you have made up your mind to lose weight, you should make that commitment and go into it with a positive attitude. Think like a winner, and envision yourself the way you want to look and feel. Don’t get discouraged if you slip now and then, and eat something you know you shouldn’t have. We’re all human. If you eat something you know isn’t good for you, enjoy it without feeling guilty. You don’t have to be perfect! It’s not what you do occasionally that counts, it’s what you do consistently on a daily basis.

Caution: Phenylalanine should not be taken by pregnant women, or those who suffer from high blood pressure, phenylketonuria, melanoma or anxiety attacks. It should not be used if taking MAO inhibitor drugs, commonly prescribed for depression.


  1. Gibbs J; Falasco JD; McHugh R Am J Physiol, 1976 Jan, 230:1, 15-18.
  2. Gibbs J; Falasco JD; McHugh R. Cholecystokinin-decreased food intake in rhesus monkeys. Am J Physiol, 1976 Jan, 230:1, 15-18.
  3. Werbach MR. Nutritional Influences on Illness. 2nd ed. Tarzana, Calif: Third Line Press; 1993:159-160, 384, 434, 494-495, 506, 580, 613-614, 636.
  4. Garrison RH Jr, Somer E. The Nutrition Desk Reference. 3rd ed. New Canaan, Conn: Keats Publishing, Inc; 1995:39-52.
  5. Haas EM. S taying Healthy with Nutrition. Berkeley, Calif: Celestial Arts Publishing; 1992.
  6. Slagle, Priscilla, M.D. The Way Up From Down, Horizon Book Promotions; 1989, Nov.